Brother MFC Series Service Manual page 61

■ Error Code 3F
Unable to print 3F
Carriage motor cannot stop.
<User Check>
- Release the release lever at the back of the Paper tray and remove the jammed
recording paper from the Engine part.
Step
1 Carriage motor harness
connection failure
2 CR encoder strip stained
3 CR encoder strip defective
4 CR encoder sensor defective
5 Carriage motor defective
6 Main PCB defective
■ Error Code 40
Unable to print 40
Casing internal thermistor problem
When the power was turned on, the casing internal thermistor detected a temperature of
-20 degrees centigrade or lower, or 80 degrees centigrade or higher.
Step
1 Casing internal thermistor
harness connection failure
2 Casing internal thermistor
defective
3 Main PCB defective
Cause
Reconnect the Carriage motor harness.
Clean the CR encoder strip.
Replace the CR encoder strip.
Replace the Carriage PCB ASSY.
Replace the Carriage motor ASSY.
Replace the Main PCB ASSY.
Cause
Reconnect the Casing internal thermistor
harness.
Replace the Ink refill ASSY.
Replace the Main PCB ASSY.
2-29
LCD
Solution
LCD
Solution
Confidential