Brother HL-4000CN - Page 225

V-15
Remedy
Step Check
Yes No
13
Checking drive PWB for signal
Print 1 sheet.
Is P/J42-29PIN<=>P/J42-14PIN
+3.3VDC?
Replace drive
PWB
Go to step [14]
14
Checking MCU and HVPS PWB for signal
Print 1 sheet.
Is P/J12-2PIN<=>P/J12-17PIN +3.3VDC?
Replace harness
ASSY DRV2
Replace MCU
and HVPS
PWB
15
Checking fuser fan
Does fuser fan function normally?
Using fuser fan diagnostic tool, check by
digital output test.
Replace MCU
and HVPS PWB
Go to step [16]
16
Checking drive PWB for signal
Print 1 sheet.
Is P/J50-7PIN<=>P/J50-9PIN +24VDC?
Go to step [19] Go to step [17]
17
Checking drive PWB for signal
Print 1 sheet.
Is P/J42-30PIN<=>P/J42-14PIN 0VDC?
Go to step [18]
Replace drive
PWB
18
Checking MCU and HVPS PWB for signal
Print 1 sheet.
Is P/J12-1PIN<=>P/J12-17PIN 0VDC?
Replace MCU and
HVPS PWB
Replace
harness ASSY
DRV2
19
Checking harness ASSY DUP for
continuity
Is J50<=>J137 continuous normally?
Go to step [20]
Replace
harness ASSY
DUP
20
Checking fuser fan
Check if an error occurs though the fuser
fan was replaced with a new one.
Replace Go to
step [21]
End of work
21
Checking drive PWB for signal
Print 1 sheet.
Is P/J50-8PIN<=>P/J50-9PIN +3.3VDC?
Fuser fan Go to step [22]
22
Checking drive PWB for signal
Print 1 sheet.
Is P/J42-27PIN<=>P/J42-14PIN
+3.3VDC?
Replace drive
PWB
Go to step [23]
23
Checking MCU and HVPS PWB for signal
Print 1 sheet.
Is P/J12-4PIN<=>P/J12-17PIN +3.3VDC?
Replace harness
ASSY DRV2
Replace MCU
and HVPS
PWB