Canon LBP5050 Series, Service Manual

Page: 84 / 104

Chapter 5
5-4
Description: The detected temperature of the main thermistor does not rise
after the heater is energised.
Cause: Main thermistor broken wire, fixer heater broken wire, DC
controller PCB defect - Check the connector of the fixing unit, DC controller PCB, fixing power
supply unit.
- Replace the fixing film unit.
- Replace the fixing power supply unit.
- Replace the DC controller PCB.
E001 Abnormally high temperature in fixing unit
0000 Description: The detected temperature of the main thermistor is
abnormally high.
Cause: Main thermistor defect, DC controller PCB defect - Check the connector of the fixing unit, DC controller PCB, fixing power
supply unit.
- Replace the fixing film unit.
- Replace the fixing power supply unit.
- Replace the DC controller PCB.
E003 Abnormally low temperature in fixing unit
0000 Description: The detected temperature of the main thermistor becomes
lower than the specified one.
Cause: Fixing power supply unit defect, main thermistor broken wire, DC
controller PCB defect - Check the connector of the fixing unit, DC controller PCB, fixing power
supply unit.
- Replace the fixing film unit.
- Replace the fixing power supply unit.
- Replace the DC controller PCB.
E004 Abnormality in fixing unit power supply drive circuitry
Description: Zero cross signal could not be detected within specified time
limit.
Cause: Fixing control circuitry defect - Check the connector of the fixing power supply unit, DC controller PCB,
fixing power supply unit.
- Replace the low-voltage power supply PCB.
E012 Motor startup abnormality
0000 Description: ITB motor speed detection signal frequency does not reach
specified frequency after starting to drive the ITB motor.
Cause: ITB motor defect, DC controller PCB defect - Check the connector of the ITB motor, DC controller PCB.
- Replace ITB motor
- Replace DC controller PCB
0001 Description: ITB motor speed detection signal frequency reaches the
specified frequency but is then out of synch after 2 sec. or longer of
operation.
Cause: ITB motor defect, DC controller PCB defect
E015 Developing roller release operation defect
0001 Description: After the specified time from rotating the main motor for the
developing roller depress/release, the output of the developing home
position sensor does not change.
Cause: Developing home position sensor defect, Main motor defect, DC
controller PCB defect - Check the connector of the developer home position sensor, main motor,
DC controller PCB
- Replace the developer home position sensor
- Replace the main motor
- Replace the DC controller PCB
E020 Density sensor abnormality
Description: Not enough light received upon image density detection.
Cause: Soiled density detection sensor, density detection sensor defect, DC
controller PCB defect, toner cartridge defect - Check the connector of the DC controller PCB.
- Replace ITB unit
- Replace DC controller PCB
- Replace toner cartridge
E024 Toner remaining detection sensor abnormality
Code Detection details Treatment