Xerox 2135DX - Phaser Color Laser Printer, Service Manual

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54 Phaser 2135 Color Printer
Missing characters or voids in print
1.
Look for dirt or contamination
on the LED heads. Clean them
with a clean, alcohol-soaked,
lint-free wipe.
2. Inspect and clean the imaging
drum unit’s power terminals
Ensure the spring-loaded pins
travel smoothly up and down.
3.
Is a low-toner condition
occurring?
4.
Replace any imaging drum
units you suspect are defective.
5. Are the LED heads’ ribbon
cables undamaged and
properly seated?
6. Is +3.8V (red wire) supplied to
Pin 3 of each LED head
assembly? If yes, replace the
LED head assembly.
7. Is +3.8 V supplied to the
POWER connector pins 1, 2, 3,
4, 5, 6, 7 and 8 on the junction board or at the 16-pin interconnect near the
top cover hinge (under the top shield plate). Inspect the junction board’s
wiring connectors. If the voltage is not OK, replace the low-voltage power
supply.
8.
If +32 volts supplied to the POWER connector pins 7, 8, 9 and 10 on the
engine controller board? Inspect the wiring harnesses or replace the
low-voltage power supply.
9.
Is +32V supplied to the HVOLT connector Pin 5 of the engine board. If not
replace the engine controller board. Transfer the old engine controller
board’s EEPROM (lower-right corner of board) to the new engine controller
board.
10. Inspect the high-voltage wiring harnesses.
11.
Replace the high voltage power supply.