Brother MFC640CW Service Manual page 264

Error Code
(Hex)
8A The paper feed motor does
not rotate.
8B The paper feed motor
stops suddenly.
8C Not used.
8D The paper feed motor
rotates in the reverse
direction.
Symptom
9 - 1 3
Probable Cause
Abnormal load applied
to the paper feed roller
PF-related gear(s)
broken
PF encoder disk
stained or scratched
PF encoder sensor
defective
Paper feed motor
defective
Main PCB defective
Abnormal load applied
to the paper feed roller
PF-related gear(s)
broken
PF encoder disk
stained or scratched
PF encoder sensor
defective
Paper feed motor
defective
Main PCB defective
PF encoder disk
stained or scratched
PF encoder disk
dislocated
PF encoder sensor
defective
Abnormal load applied
to the paper feed roller
Paper feed motor
broken
Main PCB defective
Solution
Replace the PF-related
gear(s).
Replace the PF encoder
disk.
Replace the PF sensor
PCB.
Replace the paper feed
motor.
Replace the main PCB.
Replace the PF-related
gear(s).
Replace the PF encoder
disk.
Replace the PF sensor
PCB.
Replace the paper feed
motor.
Replace the main PCB.
Replace the PF encoder
disk.
Replace the PF encoder
disk.
Replace the PF sensor
PCB.
Check the PF roller gear
and its related gears.
Replace the paper feed
motor.
Replace the main PCB.
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