Brother DCP-7090 Service Manual page 97

 Error code 6801
The side thermistor detected a temperature higher than the specified value.
<User Check>
• Lower the room temperature.
• Keep the machine away from heating appliances.
• Check that the fan is not clogged.
Step
Connection failure of the side
1
thermistor harness
2 Fuser unit thermistor failure
3 Main PCB failure
 Error code 6901
Some fuser unit errors occurred at power-ON or upon recovery from sleep mode.
Error code 6902
After the error was detected at the fuser unit, power was turned ON again and the error is
being checked. (If power is turned OFF and ON after error code 6901 occurred, this code is
displayed for about 15 minutes.)
Step
Connection failure of a fuser unit
1
harness
Connection failure of the eject
2
sensor PCB harness
3 Fuser unit failure
4 Eject sensor PCB failure
Low-voltage power supply PCB
5
failure
6 Main PCB failure
Note:
• Turn OFF the power switch. After the fuser unit has cooled sufficiently, turn ON the power
switch again and leave the machine for 15 minutes. This problem may then be cleared.
• To release the fuser unit error after taking appropriate measures, enter the maintenance
mode once and quit it with the function code 99.
Cause
Cause
2-57
Remedy
Reconnect the side thermistor harness.
Replace the fuser unit.
Replace the main PCB ASSY.
Remedy
Reconnect the fuser unit harness.
Reconnect the eject sensor PCB harness.
Replace the fuser unit.
Replace the eject sensor PCB ASSY.
Replace the low-voltage power supply
PCB ASSY.
Replace the main PCB ASSY.
Confidential