Xerox 5400N - Phaser B/W Laser Printer, Service Quick Reference Manual

Page: 62 / 503

Phaser 5400 Laser Printer Service Guide 33
General Notes on Using Repair Analysis
Procedures
1. Unless indicated otherwise, the instruction “switch ON printer main power” means
for you to switch ON printer power and let the printer proceed through power-on
diagnostics and warm-up until it is on-line and ready to print.
2. Conventions used to represent connectors:
■
P/J XX means a Plug and its corresponding Jack are connected.
■
PXX means a Plug is disconnected. (Unless this plug is soldered to a board).
■
JXX means a Jack is disconnected. (Unless this jack is soldered to a board).
3. When you are instructed to take a voltage reading between “P/J A–B and P/J
X–Y”, place the red probe (+) of your meter on pin B of P/J A, and place the black
probe (–) of your meter on pin Y of P/J X.
4. When you are instructed to take voltage readings between “P/J X and P/J Y”
(without specified pin numbers), check all voltage carrying pins. Refer to the
Wiring Diagrams for signals and pin numbers.
5. When you are instructed to take a voltage reading, the black probe (–) is generally
connected to a pin that is either RTN (Return) or SG (Signal Ground). You can
substitute any RTN pin or test point in the printer, and you can use frame ground
(frame ground) in place of any SG pin or test point.
6. Unless a Repair Analysis Procedure instructs you otherwise; before measuring
voltages make sure the printer is switched ON, the Xerographic Cartridge and the
paper trays are in place, and all of the interlock switches are actuated.
7. All voltage values given in the Repair Analysis Procedures are approximate
values. Actual measured voltages may vary more than 25% from the values stated
in the Repair Analysis Procedures. The main purpose of most voltage readings
taken in the Repair Analysis Procedures is to determine whether or not a
component is receiving the correct voltage value from the power supply and if
gating (a voltage drop) occurs during component actuation. Gating signals may be
nothing more than a pulse, resulting in a momentary drop in voltage that may be
difficult or impossible to read on the average multi-meter.
8. Repair Analysis Procedures may instruct you to remove or replace a component.
Refer to the Key FRU Removal and Replacement Procedures section for
information on how to remove and reinstall a component.
9. When a Repair Analysis Procedure instructs you to replace a non-spared
component, and that component is part of a larger assembly, you should replace
the entire assembly.
Note: Repair Analysis Procedures assume there is no malfunction
in the System Controller Board. If you are unable to fix a
problem using the Repair Analysis Procedures, it is
recommended that you replace the System Controller board.
In some instances, the Control Panel Display may not be
sufficiently functional to accurately show error codes and/or
messages. Before replacing the System Controller, please
refer to the System Controller Error Blink Code Table on
page 222 to check the LED blink codes for additional help in
troubleshooting.