Brother MFC640CW Service Manual page 262

Error Code
(Hex)
84 Recording paper jam.
(The registration sensor
stays ON after completion
of paper ejection
operation.)
85, 86 Not used.
87 The paper feed motor has
not stopped at the correct
position.
(Not used.)
Symptom
9 - 1 1
Probable Cause
The paper ejection
roller does not rotate
correctly
Foreign materials in the
paper path.
Registration sensor
actuator caught on the
surrounding parts
Registration sensor
broken
Main PCB defective
Abnormal load applied
to the paper feed roller
PF encoder disk
stained or scratched
PF encoder sensor
defective
Paper feed motor
broken
Main PCB defective
Solution
Replace the paper
ejection roller.
(Engine unit)
Remove foreign
materials.
Correct the surrounding
parts on which the
actuator caught.
Replace the PF sensor
PCB.
Replace the main PCB.
Check the PF roller gear
and its related gears.
Replace the PF encoder
disk.
Replace the PF sensor
PCB.
Replace the paper feed
motor.
Replace the main PCB.
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