Brother HL-L5000D Service Manual page 75

 Error code 3801
A temperature error occurred in the external temperature/humidity sensor.
Step
Connection failure of the
1 external temperature/humidity
sensor harness
External temperature/humidity
2
sensor failure
3 Main PCB failure
 Error code 4000
The number of rotations of the drum unit is reaching the upper limit.
Error code 4200
The number of rotations of the drum unit has reached the upper limit. (Printing does not
stop.)
Step
Replace the drum unit with a
new one and reset the drum
1
counter. If the error display is not
cleared, the main PCB is faulty.
 Error code 4500
The number of printable pages of the fuser unit has reached the upper limit.
Step
End of life of the fuser unit
1
Replace the fuser unit with a
new one and reset the fuser unit
2
counter. If the error display is not
cleared, the main PCB is faulty.
Cause
Reconnect the external temperature/humidity
sensor harness.
Replace the main frame L ASSY.
Replace the main PCB ASSY.
Cause
Replace the main PCB ASSY.
Cause
Replace the fuser unit. Refer to
counters for consumable parts (function code:
88)" in Chapter 5
after the replacement.
Replace the main PCB ASSY.
2-49
Remedy
Remedy
Remedy
"1.3.22 Reset
to reset the fuser unit counter
Confidential