Brother HL-4000CN Service Manual page 226

003-340 Firmware Error FIP
Step
Does an error occur even if the power is
turned off and on?
1
003-356 NV-RAM Error FIP
Step
Does an error occur even if the power is
turned off and on?
1
006-370 Scanner Failure FIP
Step
Checking harness ASSY scanner KA for
1
continuity
Is J15<=>P151 continuous normally?
009-340 CTD Sensor Error FIP
Step
Initial setting
1 Check the following for evidence of fault.
ADC sensor ASSY replacing condition
Checking harness ASSY CTD for
2 continuity
Is J136<=>J1361 continuous normally?
Checking harness ASSY front 1A for
continuity
3
Is J13<=>P1361 continuous normally?
Checking ADC sensor ASSY
Check if an error occurs though the ADC
4
sensor ASSY was replaced with a new
one.
Check
Check
Check
Check
V-16
Remedy
Yes
If the error
Replace MCU and recurs, replace
HVPS PWB MCU and
HVPS PWB
Remedy
Yes
If the error
Replace MCU and recurs, replace
HVPS PWB MCU and
HVPS PWB
Remedy
Yes
Replace
Replace scanner
harness ASSY
ASSY
scanner KA
Remedy
Yes
Replace the parts
Go to step [2]
concerned
Replace
Go to step [3] harness ASSY
CTD
Replace
Go to step [4]
harness ASSY
front 1A
Replace MCU and
End of work
HVPS PWB
No
No
No
No