Brother HL-4140CN Service Manual page 81

■ Error code 76
Print Unable 76
Turn the power off and then back on again.
Fuser unit error. (The center thermistor detects the sharp temperature rise.)
Error code 78
Print Unable 78
Turn the power off and then back on again.
Fuser unit error. (The center thermistor detects the sharp temperature fall.)
Step
1 Fuser unit failure
2 Low-voltage power supply PCB
failure
3 Paper eject sensor PCB failure
4 Main PCB failure
■ Error code 7A
Print Unable 7A
Turn the power off and then back on again.
Engine PCB failure (detection of motor lock error)
This error does not usually occur in the normal use. The conceivable causes are noise around
the installation site, fluctuation of the power supply voltage, and failures in the software.
<User Check>
- Turn OFF the power switch, and turn it ON again after a while.
Step
1 Engine PCB failure
2 Main PCB failure
Cause
Cause
2-50
Remedy
Replace the fuser unit.
Replace the low-voltage power supply
PCB ASSY.
Replace the paper eject sensor PCB
ASSY.
Replace the main PCB ASSY.
Remedy
Replace the engine PCB ASSY.
Replace the main PCB ASSY.
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