Xerox 4400DT - Phaser B/W Laser Printer Service Manual page 113

Main Motor Assembly Troubleshooting Procedure (cont'd.)
Step Actions and Questions
2 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. Ensure the Rear Cover is closed.
4. Switch the printer power ON.
5. Measure the Main Motor Harness Voltages listed in
the following table.
From
CN101 - Pin 1
CN101 - Pin 2
CN101 - Pin 3
CN101 - Pin 7
CN101 - Pin 8
Are all voltages correct?
3 Are the voltages on pins 1, 2, and 3 correct?
4 On the Engine Logic Board, check the voltage between
P/J28 pins 1, 2, and 3 and frame ground.
Are all three readings +24.0 VDC?
5 On the Engine Logic Board, check the voltage between
P/J30 pin 2 and frame ground.
Is the voltage +24.0 VDC?
6 Is the voltage on pin 7 correct?
7 On the Engine Logic Board, check the voltage between
P/J28 pin 7 and frame ground.
Is the voltage +5.0 VDC?
8 On the Engine Logic Board, check the voltage between
P/J28 pin 10 and frame ground.
Is the voltage +3.3 VDC?
9 1. Enter Service Diagnostics and select the Motors/Fan
Test.
2. Scroll to Main Motor but do not press OK.
3. On the Engine Logic Board, measure the voltage
between P/J29 pin 7 and frame ground.
4. Press OK to start the Main Motor test.
Does the voltage drop from +5.0 VDC to
0.0 VDC?
3-16
page
page 6-16).
To
Frame Ground
Frame Ground
Frame Ground
Frame Ground
Frame Ground
Phaser 4400 Laser Printer Service Manual
Yes
Go to step 9.
6-7), and the
Voltage
+24.0 VDC
+24.0 VDC
+24.0 VDC
+5.0 VDC
+3.3 VDC
Go to step 6.
Go to step 5.
Replace the
Engine Logic
Board (RRP
9.3 on
page
Go to step 8.
Replace the
Engine Logic
Board (RRP
9.3 on
page
Replace the
Engine Logic
Board (RRP
9.3 on
page
Replace the
Main Motor
Assembly
(RRP 8.1 on
page
No
Go to step 3.
Go to step 4.
Replace the
LVPS (RRP
9.5 on
page 6-91).
Go to step
10.
6-89).
Go to step 7.
Replace the
LVPS (RRP
9.5 on
page 6-91).
6-89).
Replace the
LVPS (RRP
9.5 on
page 6-91).
6-89).
Replace the
Engine Logic
Board (RRP
9.3 on
6-84). page 6-89).