Tektronix 1235N - Phaser Color Laser Printer, Service Manual

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52
Phaser 1235 Network Color Printer
White stripe in direction of paper travel
1. Look for dirt or contamination
on the LED heads. Clean them
with an alcohol wipe.
2.
Do the imaging drum units
make good connection to their
power terminals?
3.
Are the LED heads wiring
harnesses undamaged and
properly seated?
4.
Is +3.8V (red wire) supplied to
Pin 3 of each LED head
assembly? If yes, replace the
LED head assembly.
5.
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.
6. 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.
7. 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.
8. Inspect the high-voltage wiring harnesses.
9. Replace the high voltage power supply.