Needle Bar Cutting And Separating Does Not Occur Normally - Brother NV4000D Service Manual

Failure Investigation for Electronic Parts
5 - 16
Needle bar cutting and separating
does not occur normally
Is the needle bar cutting and
separating operation easy and
smooth?
Y
Is the resistance between pins 1 &
1, 2 & 2, 3 & 4, and 4 & 3 at the
ends of the Z pulse motor lead wire
1 Ω or less?
Y
Is the resistance across pins 1-2
and pins 3-4 for the Z pulse motor
connector 5-7 Ω?
Y
Replace main PCB assy.
Needle bar cutting and separating does not
occur normally
N
N
N
Adjust the needle-presser
module assembly
Replace the Z pulse motor
lead wire.
Replace the Z pulse motor