Brother XR9000 Service Manual page 141

Failure Investigation
for Electronic Parts
Is one of the stitch selection key,
stitch length adjustment key and
stitch width adjustment key stuck in
a pressed down condition?
Is the lead wire of the foot controller
jack assy. free from damage?
Is the foot controller jack assy.
correctly connected to the main
PCB assy. (CN4)?
5 - 18
Error is displayed
"F3" is displayed.
Y
Release the key that is stuck.
"F4" is displayed.
N
Y
Replace the main PCB assy.
Replace the operation PCB assy.
N
or
Replace the main PCB assy.
Y
Replace the foot controller
jack assy.
N
Connect it properly.