TROUBLESHOOTING GUIDE 2018.5 Ver.2.0 CSB Support Operation div.
1 Table of contents 1. Image quality..........................................................................................................................4 1.1. Spot.............................................................................................................................4 1.1.1. Cyclic white spot/black spot .................................................................................4 1.1.2. Color Spots due to soilage inside machine ..........................................................5 1.1.3. Color spots (black spots)......................................................................................9 1.1.4. White Spot due to the developing leakage (foreign material)............................. 11 1.1.5. White dots from 2nd transfer unit.........................................................................12 1.1.6. Void on solid color and attachment of powder....................................................13 1.2. Line/Band ..................................................................................................................14 1.2.1. Line and uneven density countermeasure flow ..................................................14 1.2.2. White lines (to sub-scan direction) .....................................................................17 1.2.3. Gloss line caused by fusing paper exit roller......................................................19 1.2.4. Banding in the main scan direction on halftone image printed on thick paper(Jitter problem) ...........................................................................................................................20 1.2.5. Line like ripple on image.....................................................................................23 1.2.6. Waste toner packing...........................................................................................24 1.2.7. Darker image up to 44mm from leading edge or after 44mm from white area (Developing memory) .......................................................................................................25 1.2.8. Lines or banding to the main scan direction (CD) due to speed difference between 2nd transfer and fusing.....................................................................................................26 1.2.9. Image got blurred affected by ozone (cyclic white band)....................................28 1.2.10. Photoconductor (Drum) memory ........................................................................29 1.2.11. Developing screw mark (at low speed)...............................................................31 1.2.12. Lines or banding on image due to speed change (shock noise) ........................34 1.2.13. Developing roller (44mm) cycle banding (different density)................................43 1.2.14. Irregular darker or lighter density band appears after leaving machine under high humidity environment (Green) ..........................................................................................44 1.2.15. Jittering lines at trailing edge..............................................................................45 1.2.16. 8mm interval FD lines.........................................................................................46 1.2.17. Density change by static electricity.....................................................................47 1.2.18. FD Lines and Banding........................................................................................49 1.2.19. 5mm cycle density difference caused by the fusing unit.....................................52 1.2.20. Color lines in CD at 13mm from the leading edge..............................................53 1.2.21. White line due to separation claw mark..............................................................55 1.2.22. Gloss band in CD with margin width...................................................................56 1.2.23. Image lacks at the corner of the trailing edge (Soilage in main scan direction (CD)) ...........................................................................................................................58 1.2.24. CD line on the lead edge....................................................................................59 1.3. Others........................................................................................................................61 1.3.1. Image after white part becomes darker (Developing ghost)...............................61 1.3.2. Darker at the trailing edge of image ...................................................................63 1.3.3. Background or toner scattering after continuous low coverage..........................64 1.3.4. How to maintain consistent color during continuous printing..............................65 1.3.5. Unexpected density drop if "Dens. Adj. Per Paper" set positive (+) value ..........67 1.3.6. Small blank area or color registration error ........................................................69 1.3.7. Too high gloss ....................................................................................................70 1.3.8. Rough image on the 1st side of duplex ..............................................................72 1.3.9. White or color banding at thick paper leading and trailing edges .......................73 1.3.10. C-2451, C-2452, C-2453 or C-2454, Low toner density .....................................75 1.3.11. Poor transfer at image front................................................................................76 1.3.12. Prevention of the backside soilage.....................................................................78 1.3.13. Fainted outline, darker at edge...........................................................................79
KONICA MINOLTA Confidential 2 1.3.14. Image background under high temperature .......................................................80 1.3.15. Backside image soilage......................................................................................81 1.3.16. Toner is not cleaned at the edge of the transfer belt...........................................83 1.3.17. Transferability on embossed paper ....................................................................85 1.3.18. Image density is lighter on uncoated paper (unsmooth paper)...........................92 1.3.19. Gloss memory ....................................................................................................96 1.3.20. Center of line gets broken ..................................................................................97 1.3.21. Secondary color text scatters .............................................................................98 1.3.22. Image offset caused by fusing unit ...................................................................100 1.3.23. Toner band control setting ................................................................................104 1.3.24. On the 2nd side of the small size thick paper (ex. Postcard), Uneven color occurs .........................................................................................................................107 1.3.25. Lighter density part at trailing edges of wide paper ..........................................109 1.4. Troubleshooting by using CSRA.............................................................................. 111 1.4.1. Darker/Lighter image density and background (CSRA approach).................... 111 2. Paper conveyance failure................................................................................................... 115 2.1 Others...................................................................................................................... 115 2.1.1. Paper waving.................................................................................................... 115 2.1.2. Setting for OHP sheet printing.......................................................................... 116 2.1.3. Trailing edge skews.......................................................................................... 117 2.1.4. Printed paper curls and paper feeding failure due to paper curls (without RU connection)..................................................................................................................... 118 2.1.5. Fusing wrapping jam ........................................................................................120 2.1.6. No feed jam (J-1101/J-1201)............................................................................123 2.1.7. Dents on paper at 48mm cycle in FD ...............................................................126 2.1.8. Centering error (±5 mm or more)......................................................................128 2.1.9. Paper stick with each other due to static electricity ..........................................131 2.1.10. Static Sticking in Options..................................................................................135 2.1.11. Paper removing procedure on fusing wrap up JAM..........................................138 2.1.12. J-3102, Thin paper feed failure at the 2nd transfer unit .....................................141 2.1.13. Paper wrinkle at duplex printing .......................................................................146 2.1.14. J-3201 paper is caught by the fusing separation claw......................................147 2.1.15. Corner folding at the paper leading edge, machine front side ..........................148 2.1.16. Leading edge does not looks nice (hitting mark like peeling) ...........................150 2.1.17. SRA4S Corner folding at the paper trailing edge, machine rear side ...............151 2.1.18. Pickup jam clearance workflow ........................................................................152 2.1.19. Jam, Paper damage, Image failure due to conveyance speed difference ........174 2.1.20. J-17xx/3101/3102/3120 caused by paper dust or some foreign materials attached to the feed roller..............................................................................................................181 2.1.21. Corner folding at the paper leading edge on wide paper..................................182 2.1.22. Wrinkle on thin paper at trailing edge to feed direction (on 180 to 230mm width paper) .........................................................................................................................184 2.2 Troubleshooting by using CSRA..............................................................................186 2.2.1 J-16xx (CSRA approach)..................................................................................186 3. Machine Troubles...............................................................................................................190 3.1 Control.....................................................................................................................190 3.1.1. Highlight automatic adjustment does not complete normally after trying several times .........................................................................................................................190 3.1.2. Print job is not accepted while machine indicates dehumidifying .....................191 3.2. Error code................................................................................................................192 3.2.1. C-2451, C-2452, C-2453 and C-2454 occur.....................................................192 3.2.2. C-3102 ADU wiring connector is disconnected ................................................193 3.2.3. C2455/C2456/C2457/C2458 Toner density abnormality (High density) occur..196 3.3. Others......................................................................................................................197
KONICA MINOLTA Confidential 3 3.3.1. Options cannot be recognized. System configuration display without options .197 3.3.2. How to eject developer.....................................................................................198 3.3.3. Image shift........................................................................................................200 3.3.4. Note for the developing shutter installation work ..............................................202 3.3.5. Productivity decrease at first in the morning under low temperature, low humidity 204 3.3.6. Release of productivity down mode for small size print under high temperature (Adjustment of toner band creation cycle for cleaning blade) .........................................205 3.3.7. ADU MT lever is very hard to release...............................................................207 3.3.8. Working noise of the tacking fan in the charge control unit ..............................209 4. Options...............................................................................................................................210 4.1 PF-707.....................................................................................................................210 4.1.1. Multi-feed of Plain/Fine paper under high temperature and high humidity .......210 4.1.2. PF-707m Wrinkle on paper............................................................................... 211 4.1.3. PF-707m Paper skew of small size ..................................................................213 4.1.4. PF-707m Corner fold (dog ear) and conveyance JAM of small size.................216 4.1.5. Thick paper jam due to multi-feed ....................................................................218 4.1.6. Wrinkle on thin paper at trailing edge to feed direction.....................................219 4.1.7. Light hitting mark at paper edge at PFU Registration PS phase ......................222 4.1.8. Horizontal conveyance jam at feeding thick paper (J-1624/1814/2014)..........225 4.2. LU-202XL ................................................................................................................226 4.2.1. No feed JAM/ Paper skew when feeding a western style envelop (when use MK746) .........................................................................................................................226 4.2.2. LU-202m/LU-202XL/202XLm J-1501(No feed Jam) occurs when the thick paper and the coated paper is fed. ...........................................................................................228 4.2.3. LU-202m/LU-202XL/202XLm J-1502(No feed JAM) occur when feeding coated paper .........................................................................................................................229 4.2.4. LU-202XL/202XLm Black Line at 104mm, 208mm from leading edge 614mm from trailing edge or narrow trailing space (magnification defect)...........................................230 4.2.5. Multi-feed jam of coated paper (J-1510)..........................................................231 4.3. OT-510 ....................................................................................................................232 4.3.1. J-7229 The paper trailing edge does not go out the paper exit section (Connecting OT-510) 232 4.4. FS-532.....................................................................................................................233 4.4.1. Irregular correspondence of the main tray exit .................................................233 4.4.2. FS-532/OT-510/FS-612/FS-531 Solution of Condensation under direct connection .........................................................................................................................240 4.5. IQ-501 .....................................................................................................................241 4.5.1. IQ-501, C-6A01 ................................................................................................241 4.5.2. IQ-501 and MK-744C (Patlite), C-E002/E013 ..................................................242 4.6. DF-706 ....................................................................................................................243 4.6.1. DF-706, [ADF Clean] icon appears ..................................................................243 4.7. MB-508....................................................................................................................248 4.7.1. Abnormal noise while coated paper feeding.....................................................248
KONICA MINOLTA Confidential 4 1. Image quality 1.1.Spot 1.1.1. Cyclic white spot/black spot (1) Symptom White spot/black spot repeatedly occurs at a certain cycle. (2) Cause • Drum unit Approx. 188mm cycle in a single color • Developing unit Approx. 44mm cycle in a single color • Intermediate transfer belt Approx. 861mm interval. • 1st transfer roller Approx 69mm interval • Opposing roller (?) Approx 75mm interval • 2nd transfer roller Approx. 75mm interval. • Fusing belt Approx. 311mm interval. On simplex printing, the symptom occurs on 1st side. (3) Solution After specifying the problem parts, clean and replace the subject parts. Table of contents
KONICA MINOLTA Confidential 5 1.1.2. Color Spots due to soilage inside machine (1) Symptom After pulling out the process mount and re-install it, color spots appear at the leading edge on the first ten prints. (2) Cause While pulling out the process mount, developer and toner coming out from the toner entrance and toner exit of the developing unit. It drops on the paper path, attaching to the paper and resulting in the color spots. Toner exit Toner supply opening
KONICA MINOLTA Confidential 6 (3) Solutions 1. Check the condition of toner filter box (A50UR70A) at machine left bottom. When the toner attaches too much, replace the toner filter box (Fig. 1). Then, clean following 3 locations; ● The process mount where the developing unit is installed (Fig. 2) ● Exhausting duct mouth at inside machine at machine rear (Fig. 3) ● Drum unit stay (Fig. 4). Note ● Once toner spills, when process mount is pulled out and push back, the charging corona may be soiled. To prevent that, remove all the charging coronas before pulling out the process mount. ● Do not expose the drum to the light. 2. Check whether the transfer belt cleaning unit (A50UR706) and nearby area and separation claw unit gets soiled. If it is soiled too much, clean it or replace it. Fig 1: Toner filter box, at machine rear left bottom Fig 2 Process mount Drum cartridge stay Fig. 3 Where to clean (inside machine) Fig. 4 Drum unit
KONICA MINOLTA Confidential 7 3. Check whether IDC sensor unit upper and main body ceiling gets soiled. If it is soiled too much, clean it. 4. Clean the toner at the paper path Clean the positions A, B and C with cloth (or vacuum cleaner if it is soiled too much) to (←○→) arrowed direction Note • Should not wipe to (←×→) direction because toner falls. 5. Clean the separation discharge unit with the blower brush. Clean the transfer guide plate /Up. Note • When cleaning the black sheet attached to the upper guide of 2nd transfer section of paper path, gently wipe it. Never rub firmly. If it is too dirty, replace it. When the black sheet gets torn or wavy, line or banding appear on image. • When cleaning separation discharge plate ASSY, do not touch the top of needle. If the needle got bent or broken, thin paper separation failure or line may occur. C. Paper path steel plate 2 B. Paper path steel plate 1 A. Transfer guide plate/Lw ○ × Transfer belt cleaning unit Separation claw unit Color registration unit Main body ceiling
KONICA MINOLTA Confidential 8 If the soilage still remains, remove the unit and conduct cleaning mentioned in the roller replacement procedure. 6. After cleaning, make 10 sheets of blank print in A3 to clean the paper path. Table of contents Separation discharge plate unit Black sheet
KONICA MINOLTA Confidential 9 1.1.3. Color spots (black spots) (1) Symptom Color spots (black spots) occurs Yelllow soft cakeing For human eyes, all looks like black spots on the print. (2) Cause When the temperature is high or the internal temperature increases too much, the toner or carrier forms core. Around the core, transfer failure (1st transfer/2nd transfer) occurs and spots appear. How to classify the cause Print test chart No53 with the density setting 255 and 128. See the sample through the loupe with magnification x40 and look carefully the spots. For example, the cause of spots on the magenta halftone could be attachment of carrier of other color (Y/C/K) or toner (soft clumps). So please observe carefully. In many cases, some of the above is mixed. So, take corrective action from the frequently seen symptom. • For the carrier attachment, go to (Solution "1") • For the soft clumping, go to (Solution "2" or "3") (3) Solution 1. Carrier issue Confirm that the color of the core then conduct following for the responding color. 1. Conduct Background margin fine adjustment. Service mode→[Process Adjustment]→[Process Fine Adjustment]→[Background Margin Fine Adj.] Change the setting to minus direction by 1 to 4 steps. 2. Utility/Counter →[Administrator Setting]→[System Setting]→[Expert Adjustment]→[Process Adjustment]→[Front & Back Density] Change the value by 1 to 2 steps to minus direction. After changing the setting, conduct the Gamma Automatic Adjustment. Service mode →[Process Adjustment]→[Drum Peculiarity Adjustment]]→[Gamma Automatic Adjustment] 3. Check the maximum density and if it is different from target, conduct maximum density adjustment. Print 10 pcs of test chart No53 with the density setting 255 and 128, then see the improvement level. (Confirm the variance of the occurrence.) Note • Check that AC bias and AC frequency is set to “0”. • After replacing developer to new one, print A3 with 15 % coverage by 100 sheets. The lower the Duty, the better against the color spot. However it is disadvantageous against the developing memory problem. • Front & Back adjustment is disadvantageous against white spots. • It is impossible to completely solve the soft clumping or carrier attachment issue. Yellow soft clumping Magenta soft clumping Black carrier
KONICA MINOLTA Confidential 10 However, if total 10 spots or over is seen in the entire A3 in solid or halftone, it can be improved. 2. Toner issue (environment dependent) 1. Adjust 1st Transfer (Y/M/C/K) Utility/Counter→[Administrator Setting]→[System Setting]→[Expert Adjustment]→ [Process Adjustment]→[Front & Back Density]→[1st Transfer Y/M/C/K] White Spot Change the value by every +5 Color Sport Change the value by every -5 If this step does not improve, return the value to 0 than go to step “2”. 2. Conduct toner refresh mode and check whether ejecting soft clumps is effective. Number of times of Toner refresh: Twice If following condition(s) are applicable, conduct less than twice. • Coverage (Last 5000 prints) 3% or more, and less than 5% Once 5% or more None • Life of Transfer cleaning blade 50% or more Once → If this does not improve, go to “(c) Toner issue (environment independent)”. If the symptom is improved, print 50 sheets of test chart No. 53 (with 255 setting) in the problem color on A3 to eject the soft clumping inside the developer for improvement. When further improvement is necessary, go back step 1 and change the 1st Transfer value once again. 3. Toner issue (environment independent) Clean (or replace) toner supply, toner hopper section and toner conveyance path then replace developer. Table of contents
KONICA MINOLTA Confidential 11 White spots due to the developing leakage 1.1.4. White Spot due to the developing leakage (foreign material) (1) Symptom White spots occur on the solid image. ← Paper feed direction (2) Cause Foreign material which is conductive attaches to the surface of the developing roller and abnormal discharge occurs. A conductive foreign material attaches to the developing roller surface and is conveyed to the developing nipping part. Then, it is affected by the developing AC bias, abnormal discharge occurs against the photoconductor drum. This appears as white spots. (3) Solution While checking the image, reduce the value of the Develop AC Bias Fine Adj. Service Mode →[Process Adjustment]→[Process Fine Adjustment]→[Develop AC Bias Fine Adj.] When the setting is changed, conduct gamma automatic adjustment. Note: Background, uneven density or carrier attachment may occur. Therefore, check the image when changing the settings. Table of contents
KONICA MINOLTA Confidential 12 1.1.5. White dots from 2nd transfer unit (1) Symptom Many white dots in the diameter φ0.1 to 1mm occurred. (2) Cause While transferring toner from the belt to paper, the resistance difference due to the paper generates abnormal discharge on the paper at the transfer nip. At the discharge spot on the paper, the toner repels and white spots appear on print. (3) Solution (a) At tray setting, change the 2nd transfer output 1. Change the DIPSW 1-0 from 0 to 1 to show the expert adjustment in the paper setting. [Service Mode] → [System Setting] →[Software DIPSW Setting] → DIPSW1-0:1 2. Change the 2nd transfer output corresponding to the symptom location. Machine → [Paper Setting] → [Change Set] → [Expert Adj.] At 2nd Transfer output adjustment, change the value by every +10 and find the optimum value. Note: On the thick paper, the leading edge/trailing edge transfer output is stronger or weaker than the other part. To optimize the leading edge/trailing edge, adjust the 2nd Transfer-Lead Edge and 2nd Transfer-Rear Edge in the same screen. 3. Use following paper profile. Improving image quality of fine paper(62-74gsm)NL (Released on TNBT1800082*) (b) Change 2nd transfer output in the administrator setting. When the administrator setting is used, the change is applied to all the output. If the adjustment of tray paper setting is used, the certain rate is added to the tray setting. [Utility/Counter] → [Administrator Setting] → [System Setting] → [Expert Adjustment] → [Process Adjustment] → [Front & Back Density] Check the symptom occurring side and adjust the value of the corresponding side; [2nd Transfer Front]] or [2nd Transfer Back]. Change the value by every - 10% find the optimum value. Note The transfer output at lead edge and trail edge is stronger/weaker than the other part. To optimize the leading edge/trailing edge setting, Like the step (a)-2, adjust the 2nd Transfer-Lead Edge and 2nd Transfer-Rear Edge in the same screen. (c) Change the 2nd transfer output adj. after changing the DIPSW to increase the 2nd transfer output range. [Service] →[System Setting] →[Software DIPSW] Setting→DIPSW107-4:1, DIPSW41-7:1 [Machine] →[Paper setting] →[Change Set] →[Expert: Adj.] At 2nd Transfer output adjustment, change the value by every +10 within the range 50 to 120 and find the optimum value. (d) Optimize paper state White dots is effect of the abnormal discharge of the paper. When the paper is exposed to the ambient air for days or left inside the PFU for days, the paper sometime gets dried depending on the ambient moisture. Then the symptom tends to occur easily. Try just unpacked paper. Table of contents
KONICA MINOLTA Confidential 13 1.1.6. Void on solid color and attachment of powder (1) Symptom Void (blank area) may occur on the center of the image or others. Shapes of void Points, partially blank and others A kind of powder attaches to the paper surface and stacked paper is felt dusty. (2) Cause When new paper feed roller is used, its surface may be rubbed off by the paper edge. If the dust falls on the paper and conveyed to transfer section, void occurs. Other dust and foreign material may attach to the conveyance guide upper. . (3) Solution When the void occurs, clean entire paper conveyance area. (include the guide plate of paper feeding unit) Main area of check and cleaning Basically, the area from paper feed unit to transfer unit area Clean focusing on following points.(Central area of conveyance path) Table of contents Verticality feed unit Around registunit ADU paper feed unit side
KONICA MINOLTA Confidential 14 1.2.Line/Band 1.2.1. Line and uneven density countermeasure flow (1) How to distinguish the line problem and uneven density problem 1. Conduct the gamma auto adjustment [Service Mode]→[Process Adjustment]→[Drum Peculiarity Adj.]→[Auto gamma adjustment]→ [Adjustment]→[Execute Adjustment Operation]→[Auto Gamma Adj.] * Which method you take, there is no difference in operation. 2. Print the following test pattern using paper bigger than A3 size. • No.43. Use the Dot1 screen. • Select No.53, set the density of YMCK to 120 and print the 4 color gray. • Select No.58 and set the density of MCK to 120. Use the Dot1 screen. 3. Check the print result of No.43, 53 and judge which of the following 4 patterns they apply. (a) There is line on image in the paper feed direction. (b) There is line on image crossing the paper feed direction (c) There is no line but uneven density on the entire paper. (d) Both line and uneven density can be seen. (a) Line in the paper feed direction. (b) Line crossing the paper feed direction. (c) No line but uneven density entirely. (d) Both line and uneven density exist. Paper feed direction Paper feed direction Paper feed direction Paper feed direction
KONICA MINOLTA Confidential 15 (2) Apply countermeasure per symptom (a) There is line on image in the paper feed direction Check Test pattern No.58, which was printed in Step1-(2). Check which of the following pattern [1] to [3] they apply. Apply countermeasure per pattern (a) When line is extended over the entire paper 1. Change 2nd transfer current ([Front & Back Density]) [Utility/Counter] → [Administrator Setting] → [System Setting] → [Expert Adjustment] → [Process Adjustment] → [Front & Back Density] Increase the setting value of the 2nd transfer by every 5% and check the image. If the symptom is not improved by increasing the value, try to reduce the value or change the 1st transfer value. 2. Visually check the parts and replace a problem parts Parts Chart for judge Line type Cause Intermediate transfer belt Half tone White line Scratch Color line Filming Cleaning blade Half tone/ Solid Color line Toner not cleaned 2nd transfer roller/UP Half tone/ Solid Color line Scratch, Soilage 2nd transfer roller/L Half tone/ Solid Color line Scratch, Soilage Fusing belt Solid Gloss line Scratch Fusing roller/L Solid Gloss line Scratch Note Among color lines, for the mixed color line, check the cleaning section of intermediate transfer section. If the imperfect cleaning is confirmed, replace the intermediate transfer cleaning blade. (b) When line is cut in each color Check whether the line of subject color is in dark color or void in white. Replace the probable failure parts. Parts Chart for judge Line type Cause Dev. unit (Dev. roller) Half tone/ Solid White line Scratch, Foreign material DU Half tone/ Solid White/Color line Attachment of lubricant material Charging unit (Dust proof glass) Half tone/ Solid White line Dust PH Half tone/ Solid White line Foreign material 1st transfer roller Half tone/ Solid White line Dust Feed direction 1 2 3
KONICA MINOLTA Confidential 16 (c) No line on Test pattern No.58. Line may be caused by Y. Check that the line appears in the same position on both “Test pattern No.53 in Y=120, 255” and “4 color gray test pattern” which were previously printed. And also check that the line is in colored or in white. And then replace the probable failure parts of Y. Colored line: Drum cartridge, Charging corona unit White line: Charging corona unit (b) There is line on image crossing the paper feed direction 1. Check Test pattern No.43, 53which was printed in Step(1)-2. Check the interval of line occurrence. 2. Apply countermeasure per occurrence interval. - In case of approx. 188mm pitch, scratch on the drum surface - In case of approx. 311mm pitch, scratch on the fusing upper belt - In case of approx. 44mm pitch, developing sleeve’s developer conveyance failure - In case of approx. 69mm pitch, scratch or soilage on the 1st transfer roller. - In case of approx. 75mm pitch, soilage of the 2nd transfer roller etc. Clean or replace the parts which are applicable to the pitch interval. (c) There is no line but uneven density on the entire paper 1. Conduct [Automatic Gamma Adjustment]. 2. Conduct [Color registration adjustment]. [Service mode]→[Machine Adjustment]→[Printer Adjustment]→ [Color Registration Adj.] → [Adjustment]→[Execute Adjust Operation]→[Color Registration Adj.] 3. Conduct [Highlight adjustment] [Service mode]→[Machine Adjustment]→[Quality Adjustment]→[Gamma Curve Adjustment]→[Highlight adjustment] [Utility]→[Machine Admin. Setting]→[System Setting]→[Expert Adjustment]→[Quality adjustment]→[Highlight Auto Adj.] 4. Conduct [Density Balance Auto Adjustment]. [Adjustment]→[Density Balance Adjustment] (d) Both line and uneven density can be seen 1. Remove the causes of line by conducting the countermeasure for A and B. 2. When the line became less visible, conduct the countermeasure for C. Caution When replacing the failure parts, do not jump to replace with the brand new parts but try using the old parts attached to used machines. Upon knowing how the symptom is improved with the replacement, replace with the prepared new parts. If there is no improvement by replacing parts, consider other causes. Table of contents
KONICA MINOLTA Confidential 17 1.2.2. White lines (to sub-scan direction) (1) Symptom White lines to sub-scan direction (paper feeding direction) (2) Cause (a) Line appears in single color • Charging caused line (drum potential failure) 1. When the toner soils charging grid, the grid potential control becomes poor. 2. Drum surface potential increases at the part corresponding to the soiled grid. 3. Though drum is exposed, the potential does not decrease and white line appears. • Developing unit caused line Check the bristle of developing unit of applicable color. If the line is seen in bristle, the cause is foreign material caught between developer regulating blade and unit. • Drum scratch caused line Photoconductor drum of matching color got damaged. (b) Sharp white line appears in single color • Foreign material in the laser beam path. Foreign material such as dust and toner attaches to the writing path and block laser light. It appears as line on image. (c) White line appears on black solid under high temperature and high humidity environment. • Soilage on 2nd transfer roller/Up When the 2nd transfer roller/Up is soiled, the resistance varies in feed direction. The line appears at the high resistance part because transfer ability becomes poor. (d) White line commonly appears on all colors • Soilage on 2nd transfer roller/Up • Transfer belt filming/scratch Filming tends to occur when low coverage or Feeding area of small size is frequently printed. Once the filming occurs on intermediate transfer belt, the resistance on the belt changes and poor transfer occurs. It appears as white line. (e) White band commonly appears on all colors • Transfer belt filming Paper feeding direction
KONICA MINOLTA Confidential 18 • Fusing belt shifting range (about 10mm) banding (3) Solution (a) Charging caused line (drum potential problem) 1. Clean charging grid. Use the non-woven fabric (hydro-wipe 65AA-9920). 2. Clean the charging wire with the cleaning material, equipped to the machine. 3. Replace the PH proof filter and Dust proof filters/1and 2 to new type. PH dust proof filter A50U168801 Developing dust proof filter/1 A50U168901 Developing dust proof filter/2 A50U169501 4. Change the charging corona. (b) Developing unit caused line 1. Clean the developing unit (between the developing roller and the guide plate) 2. Change the developer. 3. Change the developing unit. 4. Change the charging unit. (c) Drum scratch caused line (Scratch on the photoconductor drum of respective color) Change the drum unit. (d) Foreign material in the laser beam path Clean the soil and dust which blocks the light with unwoven fabric. (Especially, developing unit lower protruding part) (e) 2nd transfer roller/Up gets soiled 1. When 2nd transfer roller/ Up gets soiled, clean the 2nd transfer roller/Up with dry unwoven fabric. Note Do not use moisture because the line gets worse. Be sure to use dry fabric. 2. Increase density. [Paper setting]→[Change Set]→[Expart Adj.]→[Dens. Adj. Per Tray] 3. If the symptom is not solved, replace the part. (f) Transfer belt filming Conduct Belt refresh mode (Maximum one time). By one operation, A3x 5 sheets equivalent toner is consumed for cyan and magenta. [Machine]→ [Adjustment]→[Execute Adjust Operation]→[Belt Refresh mode] Note Do not perform toner refresh mode and belt refresh mode over set times. Otherwise, problem such as cleaning failure may occur. (g) Fusing belt shifting range banding Fusing belt may get marks from previous papers. If the banding is not the density level but the gloss difference corresponding to the small size paper edge, replace the fusing belt. Table of contents
KONICA MINOLTA Confidential 19 1.2.3. Gloss line caused by fusing paper exit roller (1) Symptom When printing the high coverage original, gloss line may occur on image. (2) Cause When paper passes through the fusing unit, the fusing paper exit roller and the paper surface contact each other, which lowers the temperature of contacting area. The difference of gloss level between contacting area and non-contacting area causes gloss lines. (3) Solution 1. Change pressure of the fusing paper exit roller Change pressure of the fusing paper exit roller to release position. Note • Be sure to align the knob with the mark. Do not set to unmarked position. • When releasing the fusing paper exit roller, if the length of conveyance direction (FD) is shorter than A4, paper cannot feed. However, 4 imposing postal card can feed. 2. Change of fusing temperature If the symptom is not improved enough by performing “1”, lower the fusing temperature as follows. Change DipSW1-0 to 1 to display expert adjustment in Paper Setting. [Paper Setting]→[Change Set]→[Expert Adj]→[Upper Fusing Roller Temperature] When changing the temperature, reduce by 10°C for the first step. If not enough, gradually decrease (maximum by 20°C). Print 20 sets of test pattern No. 69, and confirm that fusing under does not occur. Table of contents Default Pressure Release Knob
KONICA MINOLTA Confidential 20 1.2.4. Banding in the main scan direction on halftone image printed on thick paper(Jitter problem) (1) Symptom When printing halftone image on the thick paper, banding may appear at the 104mm and the 208mm from the leading edge of paper. *Banding mainly appears when using paper weighting 300gsm or more. Affected by the thickness and stiffness of paper, banding may appear in paper weighting less than 300gsm. (2) Cause Vibration generated when thick paper hitting the entrance When thick paper hits the 2nd transfer section entrance, slight vibration is generated. It is conveyed to the photoconductor drum through the intermediate transfer section. Consequently, the image written on the drum at the instant reflects the vibration and white banding appears. The distance between the 2nd transfer section and the drum writing position are 104mm and 208mm. (Refer to the figure below) 208mm 208mm Laser write position 104mm Feed direction
KONICA MINOLTA Confidential 21 (3) Solution 1. Change DipSW1-0 to 1 to display Expert Adjustment to Paper Setting. [Service mode]→ [System Setting]→[Software DipSW Setting] 2. In Expert Adjustment of Paper Setting, turn ON [Thick Bk mode] to ON. With this setting, even for the single Bk printing, YMC 1st transfer roller is in pressed state and that is effective to reduce vibration. [Paper Setting]→[Expert Adjustment]→[Thick Bk mode] • When the Thick Bk mode is enabled, even for the single Bk print, process related parts such as charging corona, drum, developing unit, developer, 1st transfer roller of Yellow, Magenta and Cyan is consumed. • Also, toner scattering inside machine may occur. Therefore, it is recommended to turn off the [Thick Bk mode] when it is not required. Toner scattering can be reduced by changing setting of DipSW 104-0, 104-1 (for Band creation control) Rough indication is, 3% for 3,000 pages in Thick Bk mode. However, the toner not used in the image is also consumed. Also, the paper distance is enlarged at once in every 100 pages. Consequently, the productivity decreases. Note • When the band creation control is enabled while the intermediate transfer cleaning unit reaches over the half of the limit count, cleaning failure may occur. In that case, replace the blade of the intermediate transfer cleaning unit. If the symptom is not improved enough by performing “2”, try following procedure 3. Change the setting to use lower paper weight than actual paper to increase line speed. [Paper Setting]→[Change Setting] → [Paper Weight] • 257g/m2 or more : Select 217 to 256g/m2 • 177 to 256g/m2 (For low temperature environment) : Select 92 to 105g/m2 • 177 to 256g/m2 (For other than low temperature environment): Select 136 to 176g/m2 When selecting the step 1, fusing duration is decreased and fusing problem possible occurs. To prevent that, change the Fusing upper roller temperature. [Paper Setting]→[Change Set]→[Expert Adjustment]→[Next]→[Temperature of Upper Fusing Roller] • 257g/m2 or more : Try from +5°C. If Improvement level is not enough, increase the temperature. Up to +20°C setting is available. • 177 to 256g/m2 paper with 92 to 105g/m2 setting : Try +20°C setting. • 177 to 256g/m2 paper with 136 to 176g/m2 setting : Try from +10°C. If improvement level is not enough, increase the temperature. Up to +20°C setting is available. 4. Changing the screen type. [Utility]→[Machine Admin. Setting]→[System Setting]→[Expert adjustment]→[Quality Adjustment]→[Custom Screen] • Dot175 (Screen 2 at default) is recommended. By changing from Screen 1 to Screen 2, resolution is reduced. It makes the line less visible. • After changing the screen type, perform [Highlight adjustment]. 5. If the solutions are not enough,
KONICA MINOLTA Confidential 22 Additionally, depending on paper, banding cannot be solved completely. If the improvement level is not enough, please request your customer to try another kind of paper. Table of contents
KONICA MINOLTA Confidential 23 1.2.5. Line like ripple on image (1) Symptom Unevenness in the main scan direction (CD) occurs on solid image with 2 (or more) colors. (2) Cause (a) High toner charge under the low humidity environment When toner charge is increased under the low humidity environment, the leak occurs at the 1st transfer section. (b) Excessive toner amount at the 1st transfer section When the density is high at the solid 2 color section, the leak occurs at the 1st transfer section. (3) Solution (a) High toner charge under the low humidity environment Perform the 1st transfer density adjustment. [Administrator Setting]→[System Setting]→[Expert Adjustment]→ [Process Adjustment]→ [Front & Back Density] After adjust "Front & Back Density" and return the "Machine" display, Perform automatically "Gamma automatic adjustment". Note • Increase 1st transfer current of all color(Y/M/C/K) from [Front & Back Density] by 5% for all colors then check the result. • If the symptom is not solved by increasing the 1st transfer, try to decrease the current. • Be sure to check the image during adjustment because excessive adjustment may cause following problems. Too much increase: Image memory may occur in the photoconductor drum cycle (188mm cycle). Too much decrease: White spots may occur. (b) Excessive toner amount at 1st transfer If the above procedure does not solve the problem, decrease the max density and reduce the toner amount to be transferred at 1st transfer. [Utility]→[Administrator Setting]→[System Setting]→[Expert Adjustment]→[Process Adjustment]→[Maximum Density Adjustment] After reset the transfer current adjusted at step (a) to 0, decrease the maximum density of the problem color. Change every -2 steps. Be sure to confirm if the symptom is improved. (c) When installed transfer belt/H (A9VE5001), replace to transfer belt (A1DU5042). Table of contents
KONICA MINOLTA Confidential 24 1.2.6. Waste toner packing (1) Symptom Image is soiled in paper feed direction (sub-scan direction) (2) Cause Under following condition, the temperature inside machine increases and the waste toner clumps inside the belt cleaning unit. This causes cleaning failure and toner may attach to the belt. (a) After turning OFF the sub-switch, the main switch is turned OFF though "Cooling in progress" is displayed, (b) Main power switch is turned OFF while the copy button is lighted in orange (3) Solution (a) Do not turn off the main power switch during the massage is appearing. (b) Do not turn off the main power switch during the start button is lighting in orange. Table of contents
KONICA MINOLTA Confidential 25 1.2.7. Darker image up to 44mm from leading edge or after 44mm from white area (Developing memory) (1) Symptom Darker image area up to 44mm from the leading edge. Or, darker image after 44mm from white area (text or image) < Darker area up to 44mm from the leading edge> < Darker after 44mm from white area> (2) Cause At the area before the image or white area, the toner is easily developed on to the developing roller and the toner layer is formed on the developing roller. When the roller rotates, the developer is replaced but the toner layer is not removed. (At the 1st rotation of the roller). The image density changes when the toner layer is gone (From the 2nd rotation of the roller). The density difference appears. (3) Solution 1. Change DipSW 46-2 to 1 (default: 0), to display Development output setting in the Expert adjustment. [Service mode]→[System Setting]→[Software DipSW Setting] 2. Decrease development output from the expert adjustment. Select [Down] for the Development Output Setting [Utility]→[Administrator Setting]→[System Setting]→[Expert Adjustment] →[06 Process Adjustment]→[Development Output Setting] • By the above setting, the developing duty ratio is changed from 30% (Satndard) to 50% for all colors. • When returning to normal screen, the gamma automatic adjustment is started. • When Down is selected for the Development Output Setting, banding on background may appear. Therefore, be sure to adjust carefully. Table of contents After passing white area After passing solid part 44mm 44mm
KONICA MINOLTA Confidential 26 1.2.8. Lines or banding to the main scan direction (CD) due to speed difference between 2nd transfer and fusing (1) Symptom Lines or banding occurs on thick and highly stiff paper in main scan direction (CD). (2) Cause When the print paper is thick and highly stiff, and the speed differs between the 2nd transfer and fusing unit, the banding is created at the 2nd transfer. (a) When the fusing speed is slower: Banding appears at around 130mm and 65mm from trailing edge (for A3 size) When the fusing speed is slower, the paper loop becomes larger between fusing and the 2nd transfer. When the paper is released from registration or the trailing edge of the paper passes the registration guide plates, the paper is pushed back and the banding occurs at 2nd transfer unit. Feed direction 1. Enlarged figure 130mm 65mm Leading edge Trailing edge
KONICA MINOLTA Confidential 27 (b) When the fusing speed is faster: Banding position varies When the fusing speed is faster, the paper is pulled against 2nd transfer unit. Therefore, the banding occurs at 2nd transfer section. The banding appears according to the fusing roller cycle and occurrence position on image is not constant. Unable to specify the occurrence position. (3) Solution 1. Print a test pattern with following conditions ● Paper type and weight: The same as the problem paper ● Size : A3 ● Chart : Test pattern #53 ● Color : Bk ● Density : 150 ● Quantity : 15 sheets 2. Adjust fusing speed [Machine]→ Paper Setting]→[Change Set.]→[Expert Adjustment]→[Fusing Speed Adjustment] Banding position Like Enlarged figure1 Like Enlarged figure 2 Adjustment direction [+] : Increase fusing speed [-] : Decrease fusing speed 3. Check the test pattern printed at step 1 and change the setting. 4. Repeat the above step 1 through step 3 to get the optimum settings. Note Change by 10 steps at the beginning. Continue fine tuning checking the adjustment result. Table of contents Feed direction 2. Enlarged figure Trailing edge
KONICA MINOLTA Confidential 28 1.2.9. Image got blurred affected by ozone (cyclic white band) (1) Symptom Cyclic white band occurs. ● Width of band : Width of charging corona (approx 18 to 20mm) ● Cycle : Drum (approx 188mm) (2) Cause A product resulting from ozone attaches to the surface of the photoconductor drum. Under high humidity environment, when a product resulting from ozone attaches to the photo conductor drum, it absorbs moisture. This reduces resistance of the photoconductor drum surface. Consequently, image gets blurred. (3) Solution Enable drum tiny rotation mode (a) Set auto shut off to [---min]. [Utility/Counter]→[User settings]→[System Setting]→[Power Save Setting]→ [Power Save Function Setting]→ Set --- min. for Auto Shut OFF Timer Setting. (b) Keep sub-power ON (Do not turn OFF sub-power switch) Table of contents Sub scan direction (FD) Drum cycle (approx 188mm)
KONICA MINOLTA Confidential 29 1.2.10. Photoconductor (Drum) memory (1) Symptom (a) The previous image appears as density difference at the 188 mm later position (drum rotation cycle). (b) Band in CD occurs on 1st sheet. The position is up to 58mm (or 115mm) from leading edge and up to 170mm. • It occurs only on the 1st sheet and not occurs on the 2nd sheet. • It occurs when the speed mode is selected (default setting) and not occurs in quality mode. (2) Cause (a) Symptom (a), (b) common • 1st transfer output is too much Mainly under high humidity environment, when the toner charging amount decreases, transfer output becomes too high. As the result, the image remains on the drum surface as latent image. • Drum potential decreases Mainly under high humidity environment, when the toner charge amount decreases, the developing ability increases. The lower drum potential is selected by the image adjustment. When the drum potential is low, the previous latent image affects. (b) Symptom (b) 1st transfer ON timing is reflected to the drum. 58 or 115mm 170mm Feed Direction A B C A B C 188mm Feed 通紙方向 Direction
KONICA MINOLTA Confidential 30 (3) Solution (a) Symptom (a) 1. Reduce 1st transfer [Utility/Counter]→[Administrator Setting]→[System Setting]→[Expert Adjustment]→ [Process Adjustment]→[Front & Back Density] Reduce the value for 1st Transfer Y to 1st Transfer K by 5% and check the image. Gamma automatic adjustment starts when returning to the normal screen. Note When the value is reduced too much, spots may occur. Adjust the value by the unit of 1 % and see the image. 2. Reduce developing ability [Service Mode]→[System Setting]→[Software DIPSW Setting] 1. Change the DipSW 46-2 from 0 (default) to 1. Then, the Development Output Setting can be changed. [Utility/Counter]→[Administrator Setting]→[System Setting]→[Expert Adjustment]→[Process Adjustment]→[Development Output Setting] Gamma automatic adjustment starts when returning to the normal screen. When the Development Output Setting value is reduced, transfer failure (paper surface state is reflected to image) may occur. (b) Symptom (b) Change 1st transfer output timing [Service Mode]→[System Setting]→[Software DIPSW Setting] Change DipSW 108-0 from 0 (default) to 1 • Note Since the transfer output is turned on from 1 rotation earlier, the first copy out timing slightly increases. Since number of the drum rotation increases, the drum life may be shortened slightly. When quality mode is selected, the above DipSW 108-0=1 sequence is taken regardless of the dipswitch setting. Table of contents
KONICA MINOLTA Confidential 31 1.2.11. Developing screw mark (at low speed) (1) Symptom Slant white lines in screw pitch occurs at the machine rear side, front side or whole page. (2) Cause After continuous low coverage printing After long term holiday like one week An extreme change in ambient temperature and humidity. For example, from low temperature and low humidity to high temperature and high humidity Dirt in charging unit Machine is not levelled and tilted. Machine front side is higher than machine rear side. (3) Solution Clarify the cause (a) In the case that slant white lines in screw pitch occur only at the machine rear side or in the whole page. Check the dirt of charging unit and developing unit. → Pattern 1 (b) In the case the grid in charging unit is heavily dirty by toner, replace charging unit → Refer to Pattern1 procedure_2_ note1. Feed Direction Machine rear side Machine front side Machine rear side Machine front side Rear side Whole page
KONICA MINOLTA Confidential 32 (c) In the case that slant white lines in screw pitch occur only at the machine front side. → Pattern2 Pattern 1 1. Replace developer. Note: In the case the grid in charging unit is heavily dirty by toner like following photo even if charging unit life is within PM cycle. → Replace charging unit and developing unit. 2. Change DipSW 104-7 (Defalt). It is to prevent excessive toner supply and ejection. 3. Increase developer conveyance speed at low speed [Service mode]→[System Setting]→[Software DIPSW Setting] Change the DipSW 104-4 from 0 (Normal) to 1 (Increase speed). Feed Direction Machine rear side Machine front side
KONICA MINOLTA Confidential 33 Conduct Gamma Automatic Adjustment [Service mode]→[Process Adjustment]→[Drum Peculiarity Adjustment]→[Gamma Automatic Adjustment]→[Start] Back to normal screen Note When the developer conveyance speed at low speed is increased, sharp line may be easily seen. So, when changing the setting, please confirm the actual print. 4. Execute toner band creation function (Color 5%, BK 5%). By using toner band creation function, the toner is regularly ejected from the developing unit, and fresh toner is supplied. When the less than Color / BK 5% coverage is printed continuously, toner band is created on the intermediate transfer belt to keep minimum coverage becomes Color / BK 5%. Toner band creation Dip SW Recommended Setting Default YMCK : 5% 104-0 1 0 104-1 1 0 Side effect: Toner band creation setting reduces the productivity (Reduce by max 10% for A4 conversion) and increases toner consumption at low coverage printing. When the intermediate transfer cleaning blade count reaches more than half, the cleaning failure may occur. In high-temperature and high-humidity environment, slight toner dot may occur. To prevent 2nd transfer roller getting toner dirt from toner band, change the DIPSW for 2nd transfer unit pressure release setting. DIPSW103-7 : 1 (Default: 0) Pattern2 1. Level the machine in horizontal position by using the level. Table of contents
KONICA MINOLTA Confidential 34 1.2.12. Lines or banding on image due to speed change (shock noise) (1) Symptom On the thick or the hard paper, white or color lines to CD (main scan direction) occur. Check the lines position from the following figure and specify the cause location and apply solution matching the cause. Note Depending on the paper posture, the location on the actual paper may vary by +/-10mm. • C3080 (Shifting at 2nd transfer) 89 108 252 358 266 290 Fusing nipping start Cause/Solution (a) Fusing roller contacts Cause/Solution (b) Registration roller release High speed Middle speed Low speed Exit registration guide Cause/Solution (a)
KONICA MINOLTA Confidential 35 • C3070 (Shifting at 2nd transfer) 89 108 237 359 245 265 Fusing nipping starts Fusing roller contacts Cause/Solution (b) Registration roller release High speed Middle speed Low speed Exit registration guide Cause/Solution (a) Cause/Solution (a)
KONICA MINOLTA Confidential 36 • C3080 (Shifting at 1st transfer) 193 213 356 104 34 370 394 Previous sheet exit 2nd transfer Enter to 2nd transfer Fusing roller contact Fusing nipping starts Cause/Solution (b) Cause/Solution (c) Cause/Solution (a) Release registration roller High speed Middle speed Low speed Cause/Solution (b)
KONICA MINOLTA Confidential 37 • C3070 (Shifting at 1st transfer) 193 213 341 104 33 350 370 High speed Low speed Previous sheet exit 2nd transfer Enter to 2nd transfer Fusing roller contact Fusing nipping starts Release registration roller Cause/Solution (b) Cause/Solution (c) Cause/Solution (a) Cause/Solution (b)
KONICA MINOLTA Confidential 38 • C3080 (Shifting at write unit) 297 317 208 76 138 143 139 82 77 Previous sheet exit registration guide Cause /Solution (a) Cause/Solution (b) Cause/Solution (c) Cause/Solution (a) High/Low speed Middle speed Previous sheet exit 2nd transfer Enter to 2nd transfer Fusing roller contacts Fusing nipping starts High/Low speed Middle speed
KONICA MINOLTA Confidential 39 • C3070 (Shifting at write unit) Previous sheet exit registration guide High speed Middle speed Low speed Cause/Solution (a) Previous sheet exit 2nd transfer High speed Middle speed Low speed Cause/Solution (b) Enters 2nd transfer Cause /Solution (c) Cause/Solution (a) Fusing roller contacts Fusing nipping starts 297 317 208 33 94 108 137 47 75
KONICA MINOLTA Confidential 40 (2) Cause (a) Changes due to the paper behavior at 2nd transfer When the paper enters to the fusing unit or exits from the registration guide plate and force relation at 2nd transfer is changed by the paper, the shifting occurs at the 2nd transfer. Or if it is conveyed to the intermediate transfer belt, shifting occurs at 1st transfer or write unit. (b) Changes due to the speed difference between fusing unit and the 2nd transfer. Depending on the paper hardness, the paper is pulled, pushed or goes back between 2nd transfer and fusing unit. Consequently, 2nd transfer shifts occurs. Or if it is conveyed to the intermediate transfer belt, shifting occurs at 1st transfer unit or write unit. (c) Changes due to the paper behavior between registration unit and 2nd transfer unit. Depending on the paper position between registration and 2nd transfer unit, the paper which is just before 2nd transfer nipping is pulled or pushed or goes back between registration unit and 2nd transfer unit. It is conveyed to the transfer belt and shifting occurs at 1st transfer or write unit. Mechanism of shifting at 2nd transfer • Fusing roller speed < Registration roller speed (2nd transfer roller speed) • Fusing roller speed > Registration roller speed (2nd transfer roller speed) ･ Fusing roller speed << Registration roller speed (2nd transfer roller speed) The loop is formed between 2nd transfer and fusing unit When the registration is released, the loop between 2nd transfer and fusing unit is released, the loop is released and shifting occurs at the 2nd transfer. The paper is pulled between 2nd transfer and fusing When the registration is released, fusing unit pulls the paper and shifting occurs at 2nd transfer When the paper enters to the fusing and nipped, by the roller and 2nd transfer unit. The registration roller pushes the paper and the loop is formed just before the fusing unit. It is released when the registration is released. The loop is pushed back and shifting occurs at 2nd transfer. Fusing roller Vt 2nd transfer roller Vt Registration roller Vr Goes back Pulled Stopped here
KONICA MINOLTA Confidential 41 Mechanism of shifting at 1st transfer At the 1st transfer position, the shifting occurs due to the speed difference between the intermediate transfer belt and the drum. Belt speed > Drum speed: White line Belt speed < Drum speed: Black line The banding width varies depending on the degree of the change; lines or blurred banding occurs Mechanism of shifting at Write position Write position shifts by the drum speed difference Drum speed > 0: White line Drum speed < 0: Black line The banding width varies depending on the degree of the frequency change; relatively clear lines occur. Paper speed constantly slows down at 2nd transfer unit and image gets blurred. When the loop is not formed enough, the paper speed is slowed down and blurred image or banding appears. Drum Vb Vｄ 1st transfer position Intermediate transfer belt Drum PH Vd Write position Vd± Δ Vd
KONICA MINOLTA Confidential 42 (3) Solution (a) Lines due to the paper behavior at the 2nd transfer 1. Check 2nd transfer pressing release mechanism works normally. 2. 1st transfer misalign and write position shift occurs due to vibration when paper insert in 2nd transfer. To reduce the force change influence, reduce the 2nd transfer pressure. 3. To reduce the force change influence at the 2nd transfer when paper insert in the fusing roller, increase the 2nd transfer pressure. 4. Check if the fusing guide plate/front is installed normally, (bending or fitting state of guide plate) (b) Lines due to the speed difference between the fusing and the 2nd transfer 1. Check the fusing roller rotation status (Whether roller rotation is smooth). 2. Check if the pressure release mechanism is normal. 3. Adjust fusing speed to depress the influence of the force change. (c) Lines due to the paper behavior at parts between the registration and the 2nd transfer 1. Swap the drum with other color to see the state. 2. Check the guide plates upstream of the 2nd transfer. Table of contents
KONICA MINOLTA Confidential 43 1.2.13. Developing roller (44mm) cycle banding (different density) (1) Symptom Lighter or darker density bands appear at 44 mm cycle in CD direction. (2) Cause Due to the developing roller deflection within the tolerance, Ds or Developer conveyance amount changes. Depending on the deflection level of the roller, developing efficiency of the photoconductor drum changes and the symptom occurs. (3) Solution To enhance developing ability, increase the Develop AC Bias Fine Adj. setting while checking the adjustment result. Service Mode → [Process Adjustment] →[Process Fine Adjustment] →[Develop AC Bias Fine Adj.] When the setting is changed, conduct gamma automatic adjustment. Note Background, white spot or carrier attachment may occur. Therefore, check the image when changing the settings. Table of contents 44mm cycle
KONICA MINOLTA Confidential 44 1.2.14. Irregular darker or lighter density band appears after leaving machine under high humidity environment (Green) (1) Symptom When the machine is left under high temperature and high humidity environment for long period, darker or lighter density band occurs in 2-color solid (green). It is not cyclic bands. (2) Cause When the machine is left under high temperature environment, the charge of the toner in the developing unit becomes low. This causes the high developing efficiency at the print start timing and the lines of different density created by the fine potential/fine vibration become visible. (3) Solution 1. To increase toner charge amount, perform toner refresh mode. [Utility/Counter] → [Administrator Setting] → [System Setting] → [Expert Adjustment] → [Execute Adjust Operation] → [Toner Refresh Mode] → Going back to usual screen, the toner refresh is conducted. Number of times of Toner refresh: Twice If following condition(s) are applicable, conduct less than twice. Coverage (Last 5000 prints) 3% or more, and less than 5% Once 5% or more None Life of Transfer cleaning blade 50% or more Once 2. It the step 1 does not solve the symptom, adjust the max density to achieve higher density. [Utility/Counter] → [Administrator Setting] → [01System Setting] → [05 Expert Adjustment] → [06 Process Adjustment] → [02Maximum Density Adjustment] → Adjust the Y and C maximum density to the darker value. Going back to usual screen, the Automatic Gamma adjustment is conducted. 3. Conduct print and increase toner charge amount. Print test patter No53, with Y and C gradation adjustment to 255 in A4 size and 100 sheets. Table of contents
KONICA MINOLTA Confidential 45 1.2.15. Jittering lines at trailing edge (1) Symptom Color lines or white lines occur at the one cycle of the fusing belt (310mm) from the trailing edge of the previous sheet. (2) Cause The potential at the trailing edge of the thick paper is high. It remains on the fusing belt and affect on the next sheet image; scatters (color lines) or repels the toner (white line) on the image. (3) Solution (a) Widen the distance between papers (decrease CPM) • Change the DipSW1-0 from 0 (Default) to 1 to show Expert adjustment. • Copy Screen (Machine screen) → [Paper Setting]→[Change Set]→[Expert Adj.] • Select [Down] for [CPM Down]. Note The productivity becomes one half so if it is not acceptable, take the solution (b). (b) Adjust the Separation DC. 1. Change the DipSW1-0 from 0 (Default) to 1 to show expert adjustment. 2. Adjust Separation DC in the Expert adjustment. Copy Screen (Machine screen)→[Paper Setting]→[Change Set]→[Expert Adj.], 3. Increase [Separation DC (Front)]. Note: When the separation DC is increased, the following symptom may occur. Do not increase much. • Plain paper Noise from static electricity appears on image • Coated paper Unable to control Wrinkle, Poor separation Noise from static electricity appears on image (c) Check the paper state • Use the paper just unpacked. (When the moisture in the paper is low, the symptom occurrence increases.) • When the PF-707 heater is turned ON during night, turn OFF it. Note When the humidity is high and the heater is turned OFF, watch the lighter image density and wrinkles. Table of contents 前紙後端 通紙方向 310㎜ （定着ベルト1周分） 前紙 Previous sheet Feed direction Trailing edge of the previous sheet (1cycle of fusing belt) 310mm
KONICA MINOLTA Confidential 46 1.2.16. 8mm interval FD lines (1) Symptom After replacing the drum unit to new one, multiple FD lines in 8mm interval occur. (2) Cause Uneven transfer due to the uneven condition of the transfer belt surface. Up to 2000 prints after replacing drum unit to new one, the lubricant is gradually transferred to the transfer belt then saturated. Meanwhile, the belt surface condition becomes uneven and uneven transfer occurs. The symptom tends to occur especially when the transfer belt, drum unit, intermediate transfer belt and intermediate transfer cleaning unit are replaced as a set. 8mm interval is caused by the configuration of the auxiliary roller inside the intermediate transfer cleaning unit. (3) Solution To turn the unit to used condition, conduct color registration automatic adjustment. Press [Utility/Counter]→[Administrator Setting]→[System Setting]→[Expert Adjustment]→[Execute Adjust Operation] →[Color Regist. Auto.Adj]. Press OK then go back to the usual screen. Adjustment is executed. If the lines cannot be reduced, repeat it once more. However, the maximum times of execution is 3 times. Because the cleaning blade failure may occur. Table of contents 通紙方向 8mm間隔の FDスジ複数 Feed Direction Multiple FD lines in 8mm interval
KONICA MINOLTA Confidential 47 1.2.17. Density change by static electricity (1) Symptom (a) At the 40mm to 160mm from the leading edge of paper, the different density area appears in FD direction. (b) At the approx. 50mm and 310mm from the leading edge of paper, the different density area in FD direction appears. (2) Cause (a) Excessive neutralization The excessive neutralization current is applied to paper then the static electricity suction power between paper and toner is decreased. With this state, when the paper enters to the fusing nip, the image is affected by the electric field and image scatters and density looks darker. (b) Excessive neutralization Due to the same cause as (a), the static electricity suction power decreases. Unfused toner is affected by the electric field strongly and attach to the fusing belt. The toner attaches to the fusing belt is fused on the image after one cycle of the fusing belt. Where the toner is removed looks lighter and additional toner attached looks darker. (3) Solution Adjust the neutralization current 1. Change the DipSW1-0 from 0 (Default) to 1 to show expert adjustment. 通紙方向 用紙先端 40～50㎜ 約160㎜ 40～50㎜ 通紙方向 用紙先端 画像先端 （定着ベルト1周） 310㎜ Feed Direction From lead edge 40 to 50 mm and approx. 160mm Feed Direction Paper lead edge (One cycle of Fusing belt) 310mm 40 to 50mm from Paper lead edge
KONICA MINOLTA Confidential 48 2. Adjust Separation DC current. Copy screen (Machine screen)→[Paper Setting]→[Change Set]→[Expert Adj.] Adjust Separation Current. 3. Decrease Separation DC (Front) 4. Decrease Separation AC (Front) Note Please mind that after decreasing separation current, the thin paper behavior may not be stable and wrinkle, feed failure may occur on thin paper. Do not adjust excessively. Table of contents
KONICA MINOLTA Confidential 49 Feeding direction 1.2.18. FD Lines and Banding (1) Symptom Black (or Gray) lines and bands in the feeding direction occurs on printout as well as on the surface of the intermediate transfer belt. (2) Causes (a) Damage on the edge of the belt cleaning blade The position of lines are always the same because the edge of the cleaning blade is chipped or malformed for some reasons. It does not matter condition, paper type or job type, it happens when printing. (b) Clumps stuck between the blade and the transfer belt Lubricant and paper dust forms clumps. Too much clumps stuck between the cleaning blade and the transfer belt. Then cleaning failure occurs. The position of lines are random. The condition to make much clumps is; Low coverage (less than 3%) prints Low to high coverage prints Plain and fine paper (produce much paper dust) Cause 1: Chipping cleaning blade