[C][M][Y][K] Imaging Unit Failure - Xerox Phaser 7400 Service Manual

[C][M][Y][K] Imaging Unit Failure

The Drum Phase Sensor for the named Imaging Unit indicates that the drum is out of
position.
Applicable Status Codes:
Code U26: Yellow Imaging Unit Failure
Code U27:
Magenta Imaging Unit Failure
Code U28: Cyan Imaging Unit Failure
Code U29: Black Imaging Unit Failure
Initial Actions:
Reseat the indicated Imaging Unit
Cycle the printer's power.
If the problem persists follow the procedure below.
Troubleshooting Reference Table
Applicable Parts
[C][M][Y][K] Imaging Unit, PL1.1.23
[C][M][Y][K] I/U Motor, PL2.1.8
I/U Sensor Board, PL5.1.21
I/U Lift Uplink, PL6.1.4, PL5.1.11
Troubleshooting Procedure Table
Step Actions and Questions
1 Check the following for evidence of fault or
damage:
Imaging Unit
Imaging Unit Drive Gears
Imaging Unit Sensor Board
Imaging Unit Lift Uplink
Is there any damage?
2 Test the Drum Phase Sensor.
Run the Service Diagnostics Drum Phase
Sensor test for the indicated Imaging Unit.
Does the sensor function correctly?
3 Check the I/U Phase signal:
CIDPHASE at CTG1-18
MIDPHASE at CTG1-20
YIDPHASE at CTG1-22
KIDPHASE at CTG1-24
Does the Drum Phase signal change when
the sensor is blocked?
Error Messages and Codes
Wiring and Plug/Jack References
Print Engine Map 5 (page 10-8)
Print Engine Map 8 (page 10-11)
Print Engine Imaging Unit Sensor Board (page 10-41)
Print Engine Motor Driver Board (3/6) (page 10-33)
Yes
Replace any
damaged parts.
Go to Step 5
Go to Step 4.
No
Go to Step 2.
Go to Step 3.
Replace the I/U
Sensor Board
(page 8-142).
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