Brother DCP-7030 Service Manual page 31

■ Error code 78
Print Unable 78
See Troubleshooting and routine maintenance chapter in User's Guide.
Fuser unit failure (The temperature sensor of the fuser unit is broken.)
Step
1 Fuser unit failure
2 Main PCB failure
■ Error code 79
Print Unable 79
See Troubleshooting and routine maintenance chapter in User's Guide.
No detection of the internal temperature thermistor.
Step
Harness connection failure of
1
internal temperature thermistor
Internal temperature thermistor
2
failure
3 Main PCB failure
■ Error code 7A
Print Unable 7A
See Troubleshooting and routine maintenance chapter in User's Guide.
No detection of the main motor lock signal.
Step
1 Main motor failure
2 Main PCB failure
■ Error code 7B
Print Unable 7B
See Troubleshooting and routine maintenance chapter in User's Guide.
Main PCB failure
Step
1 Main PCB failure
Cause
Cause
Cause
Cause
1-13
Remedy
Replace the fuser unit.
Replace the main PCB ASSY.
Remedy
Check the harness connection of the internal
temperature thermistor, and reconnect it.
Replace the internal temperature
thermistor.
Replace the main PCB ASSY.
Remedy
Replace the main motor ASSY.
Replace the main PCB ASSY.
Remedy
Replace the main PCB ASSY.
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