Brother HL-4000CN, Service Manual, Page: 247 / 345

V-37
Upper Cassette Detached FIP
Remedy
Step Check
Yes No
1
Initial setting
Check the following for evidence of fault.
Size switch ASSY replacing condition
actuator replacing condition
Paper cassette replacing condition
Replace the parts
concerned
Go to step [2]
2
Checking size switch ASSY
Does size switch ASSY function normally?
Size switch ASSY using diagnostic tool,
check by digital input test.
Replace MCU and
HVPS PWB
Go to step [3]
3
Checking drive PWB for signal
Check the following, and does the result
meet the combination table?
P/J47-1PIN<=>P/J47-3PIN
P/J47-2PIN<=>P/J47-3PIN
P/J47-4PIN<=>P/J47-3PIN
Refer to paper size control of operation
principle
Go to step [4]
Replace size
switch ASSY
4
Checking drive PWB for signal
Check the following, and does the result
meet the combination table?
P/J42-16PIN<=>P/J42-15PIN
P/J42-17PIN<=>P/J42-15PIN
P/J42-18PIN<=>P/J42-15PIN
Replace MCU and
HVPS PWB Replace drive
PWB
Tray1 Paper Near Empty FIP
Remedy
Step Check
Yes No
v
Initial setting
Check the following for evidence of fault.
Tray1 low paper sensor replacing
condition
Sensor actuator replacing condition
Replace the parts
concerned
Go to step [2]
2
Does the error occur even if the paper is
added?
Go to step [3] End of work
3
Checking tray1 low paper sensor
Does tray1 low paper sensor function
normally?
Tray1 low paper sensor using diagnostic
tool, check by digital input test.
Replace MCU and
HVPS PWB
Go to step [4]
4
Checking drive PWB for signal
Is P/J47-10<=>P/J47-9 +3.3VDC?
Go to step [6] Go to step [5]
5
Checking drive PWB for signal
Is P/J42-20<=>P/J42-15 +3.3VDC?
Replace drive
PWB
Replace MCU
and HVPS
PWB
6
Checking drive PWB for signal
Is P/J47-8<=>P/J47-9 +3.3VDC? Replace tray1 low
paper sensor Replace drive
PWB