Brother HL-4000CN Service Manual page 240

Yellow Toner Empty FIP
Step
Initial setting
Check the following for evidence of fault.
1 Low toner sensor replacing condition
Toner cartridge replacing condition
Toner motor replacing condition
Checking toner cartridge
2 Check if an error occurs though the
cartridge was replaced with a new one.
Checking drive PWB for signal
3 Is P/J51-16<=>P/J51-15 less than
+0.2VDC?
Checking harness ASSY TNR for
4 continuity
Is J441<=>J51 continuous normally?
Checking low toner sensor
5 Check if an error occurs though the low
toner sensor was replaced with a new one.
Checking harness ASSY DRV2 for
6 continuity
Is J12-23<=>J42-8 continuous normally?
Checking toner motor
Does toner motor function normally?
7 Using toner motor, check by digital output
test.
In the test, close the interlock SW.
Checking drive PWB for signal
8
Is P/J51-1<=>P/J60-2 +24VDC?
Checking harness ASSY TNR for
9 continuity
Is J511<=>J51 continuous normally?
Checking toner motor
10 Check if an error occurs though the toner
motor was replaced with a new one.
Checking harness ASSY DRV1 for
continuity
Check the following for continuity.
11 J11-25<=>J41-16
J11-26<=>J41-15
J11-27<=>J41-14
J11-28<=>J41-13
Check
V-30
Remedy
Yes
Replace the parts
Go to step [2]
concerned
Go to step [3] End of work
Go to step [4]
Go to step [6]
Replace
Go to step [5] harness ASSY
TNR
Go to step [6] End of work
Replace
Go to step [7] harness ASSY
DRV2
Check the toner
stirring auger or Go to step [8]
gear for damage
Replace drive
Go to step [9]
PWB
Replace
Go to step [10] harness ASSY
TNR
Go to step [11] End of work
Replace drive
PWB, and if still Replace
faulty, replace harness ASSY
MCU and HVPS DRV1
PWB
No