Lower Thread Is Not Trimmed (Pulls When Material Is Removed); Feed Mechanism Does Not Operate Or Motor Is Out Of Step - Brother HE-800B Instruction Manual

11. TROUBLESHOOTING

11-25. Lower thread is not trimmed (pulls when material is removed)

Items with a "*" in the "Page" column should only be handled by a qualified technician.
Cause
Fixed knife set

11-26. Feed mechanism does not operate or motor is out of step

Items with a "*" in the "Page" column should only be handled by a qualified technician.
Cause
Feed motor
Upper thread trimmer
Feed home position
sensor
Feed timing belt
95
Check
Fixed knife and movable
knife do not mesh.
Knife tip is bent or chipped.
Check
Cord connection
Upper thread trimmer
position
Check if the cam opens the
stop plate.
Feed home position sensor
position
Feed timing belt tension
Remedy
Adjust the fixed knife set installation position.
Fixed knife
Repair or replace the knife.
Remedy
Check if there are any problems with the connection
and contacts of feed motor connector P22 on the main
P.C. board.
Remove and re-install the upper thread trimmer.
Install so that the projection on
trimmer M is not inserted.
* Always make sure that the upper
thread trimmer is in the correct
position before use.
Adjust the cam position.
* If the feed mechanism operates when the cam has
not opened the stop plate, the cutter will bump
against the upper thread trimmer.
Adjust the feed home position sensor position.
Adjust the feed timing belt.
HE-800B
Page
*
Movable knife
4024Q
*
Page
10*
*
4895M
69*
4018Q
*
*