Xerox Phaser 8400 Service Manual page 204

Electronics Troubleshooting Guide
Short circuit With power cord connected, touch the
on 3.3V metal Electronics Module to discharge
power any static electricity.
supply
within the
Electronics
Module
Turn off printer and wait 30 seconds for
power supply capacitors to discharge
Unplug power cord and remove printer's
covers
Unplug the following Electronics Module
connectors:
1) Power Control to I/O board ('P' / J800),
2) Power Control right ('Q' / J400),
3) Printhead data ('CE' / J130),
4) Waveamp signal ('AK' / J790),
5) Power Control left ('AI' / J390),
6) Y-axis motor ('AH' / J280)
Plug in power cord and turn on power to
the printer
If the PE and PS indicators do not flash,
the short is inside the Electronics Module.
Replace the Electronics Module and
retest the printer. If PE and PS indicators
flash, continue with debug.
Plug in all cables removed during service
Attach printer covers
Perform full test of printer
General Troubleshooting
ESD damage to the
printer may occur if
static electricity is
discharged to printer
electronics
Damage to circuits
within the Electronics
Module may occur if
the power supply
capacitors are not
allowed to fully
discharge
Use caution around
motors, pulleys and
live AC connections
when working with
the printer covers off
This step removes all
other circuits so the
Electronics Module
can be tested alone
* Possible solution to
problem *
Trace through all
service steps
performed to
reattach any cables
that were unplugged
during debugging
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