Brother HL-4040CN Service Manual page 54

Error code E6
Print Unable E6
Turn the power off and then back on again.
NVRAM error on main PCB
Step
1 Main PCB failure
Error code EB
Print Unable EB
Turn the power off and then back on again.
NVRAM reading error on laser unit
Step
1 Harness connection failure
between laser unit and main
PCB
2 Laser unit failure
3 Main PCB failure
Cause
Replace the main PCB ASSY.
Cause
Check the harness connection between the laser
unit and main PCB and reconnect it.
Replace the laser unit.
Replace the main PCB ASSY.
1-37
Remedy
Remedy
Confidential