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CHAPTER 6 TROUBLESHOOTING
6-21
M-8
Scanner failure
Possible cause
Step
Check
Result
Remedy
Harness
connection
failure
1
Is the connection of the
scanner motor connector P12
on the engine PCB secure?
No
Reconnect the connector
securely.
Power supply
input
2
Is the voltage between pins 1
(+24V DC) and 2 (GND) of
connector P12 on the engine
PCB 24V DC?
No
Check if +24V DC is supplied
between pins 2 (+24V DC) and
3 (+24V RET) of connector P5
on the engine PCB. If not,
check the power supply output
on the low-voltage power
supply PCB.
Yes
Replace the laser unit.
M-9
Fuser failure
Possible cause
Step
Check
Result
Remedy
Poor thermistor
harness contact
1
Is the contact of connector P6
on the engine PCB good?
No
Reconnect the connector.
Blown thermal
fuse
2
Remove the fixing unit and
measure the resistance
between the input connectors.
Is it open circuit?
Yes
Replace the fixing unit.
Thermistor
failure
3
Is the thermistor installed
properly?
Yes
Replace the fixing unit.
No
Reinstall the thermistor
properly.
Halogen heater
lamp failure
4
Remove the fixing unit and
measure the resistance of the
halogen heater lamp. Is it
open circuit?
Yes
Replace the halogen heater
lamp.
Heater harness
connection
failure
5
Is the heater harness
connector connected to the
low-voltage power supply PCB
and fixing unit secure?
No
Reconnect the connectors
securely.
NOTE:
·
This problem will be cleared if leaving the printer power ON for ten minutes.
·
If the heater is cooled down sufficiently, this problem may be cleared by turning on the
printer power switch while pressing the panel button. Be warned, however, that this
operation will melt the fixing unit if the heater is hot.
Summary of Contents for HL-1240
Page 1: ......
Page 45: ...CHAPTER 3 THEORY OF OPERATION 3 7 Fig 3 6 ...
Page 102: ...CHAPTER 4 DISASSEMBLY AND RE ASSEMBLY 4 38 ...
Page 110: ...CHAPTER 5 PERIODIC MAINTENANCE 5 8 ...
Page 176: ...CODE UK4352000 B512040CIR 1 2 A 18 NAME Appendix 10 Main PCB Circuit Diagram HL 1240 1 2 ...
Page 177: ...Appendix 11 Main PCB Circuit Diagram HL 1240 2 2 CODE UK4352000 B512040CIR 2 2 A 19 NAME ...
Page 178: ...Appendix 12 Main PCB Circuit Diagram HL 1250 1 5 CODE UK4361000 B512049CIR 1 5 A 20 NAME ...
Page 179: ...Appendix 13 Main PCB Circuit Diagram HL 1250 2 5 CODE UK4361000 B512049CIR 2 5 A 21 NAME ...
Page 180: ...CODE UK4361000 B512049CIR A 22 NAME Appendix 14 Main PCB Circuit Diagram HL 1250 3 5 ...
Page 181: ...CODE UK4361000 B512049CIR 4 5 A 23 NAME Appendix 15 Main PCB Circuit Diagram HL 1250 4 5 ...
Page 182: ...CODE UK4361000 B512049CIR 5 5 A 24 NAME Appendix 16 Main PCB Circuit Diagram HL 1250 5 5 ...
Page 183: ...Appendix 17 Engine PCB Circuit Diagram CODE UK4444000 B512059CIR A 25 NAME ...
Page 192: ...INDEX vi ...
Page 321: ...A 12 HP LaserJet IIP HP LaserJet 6P HL 1250 only ...
Page 323: ...A 14 HP LaserJet IIP 6P EPSON FX 850 IBM Proprinter XL EPSON FX 850 ...