Xerox 4400DT - Phaser B/W Laser Printer Service Manual page 129

HVPS Assembly Troubleshooting Procedure (cont'd.)
Step Actions and Questions
2 1. Cheat the Front Cover Interlock Switch.
2. Enter Service Diagnostics and select Component
Checks.
3. Scroll to each of the high voltage tests listed in High
Voltage Power Supply Readings table on
4. Measure the voltage between the contact listed and
frame ground.
5. Press the Enter Key.
Is at least one of the voltages correct?
3 1. Switch the printer power OFF.
2. Remove the Left Interface Cover (RRP 1.1 on
page 6-6), Left Cover (RRP 1.2 on
Left Plate (RRP 1.11 on
3. Switch the printer power ON.
4. On the Engine Logic Board, check the voltage
between P/J26 pin 2 and frame ground.
Is the voltage +24 VDC?
Are all the voltages correct?
4
5 1. Replace the Engine Logic Board (RRP 9.3 on
page 6-89).
2. Cheat the Front Cover Interlock Switch.
3. Enter Service Diagnostics and select Component
Checks.
4. Scroll to each of the high voltage tests
5. Measure the voltage between the contact listed and
frame ground. Press the Enter Key.
Are all the voltages correct?
6 Check the Transport Chute Assembly for proper
installation.
Is the Transport Chute properly installed?
7 Check the HVPS harness for proper connection and for
damage.
Is the harness damaged or improperly
connected?
High-Voltage Power Supply Readings
High-Voltage Test
Charge Roller DC
Charge Roller AC
Developer Bias DC
Developer Bias AC
Bias Transfer Roller -
Bias Transfer Roller +
Detack Saw
3-32
page
page 6-7), and the
page 6-16).
(page
Contact
Rear Transport Chute Pin Contact -425 ±40 VDC
Rear Transport Chute Pin Contact 1000 ± 100 VAC
Front Transport Chute Pin Contact +4.3 ± 3 VDC
Front Transport Chute Pin Contact 555 ± 55 VAC
Transfer Roller Bushing
Transfer Roller Bushing
Detack Saw
Phaser 4400 Laser Printer Service Manual
Yes
Go to step 4.
3-32.
Replace the
HVPS (RRP
9.6 on
page 6-92).
Problem
solved.
Problem
solved.
3-32).
Go to step 7.
Replace the
HVPS (RRP
9.6 on
page 6-92).
Reading
-81 ± 8 VDC
0 VDC
-930 ± 100 VDC
No
Go to step 3.
Replace the
Engine Logic
Board (RRP
9.3 on
page 6-89).
Go to step 5.
Go to step 6.
Install the
Transport
Chute
correctly.
Repair or
replace the
HVPS
harness as
necessary.