6. Adjustment................................................................................................... 358
Pickup Feed System....................................................................................................................... 359
Image Position Adjustment.................................................................................................................359
Original Exposure System...............................................................................................................367
Reader Unit...................................................................................................................................... 367
Original Feed System......................................................................................................................368
Adjusting the Height.......................................................................................................................... 373
Light intensity adjustment ..................................................................................................................381
White Level Adjustment .................................................................................................................... 383
Parallelogram Correction................................................................................................................... 386
Other Adjustments.............................................................................................................................396
Main Controller PCB..........................................................................................................................404
SSD................................................................................................................................................. 405
MP Pickup Tray Unit..........................................................................................................................408
Control Panel Unit............................................................................................................................. 408
Laser Scanner Unit............................................................................................................................409
Developing Assembly........................................................................................................................ 409
Registration Sensor Unit.................................................................................................................... 410
Scanner Unit (Paper Front)................................................................................................................ 410
Scanner Unit (Paper Back).................................................................................................................411
Copyboard Glass.............................................................................................................................. 412
7. Troubleshooting...........................................................................................413
Initial Check.....................................................................................................................................414
Test Print......................................................................................................................................... 415
Overview.......................................................................................................................................... 415
How to use the test print.................................................................................................................... 416
Troubleshooting Items.....................................................................................................................422
Forcible stop of paper feed.................................................................................................................424
toner concentration sensor............................................................................................................. 430
Controller Self Diagnosis.................................................................................................................432
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Contents