The Touch Panel Does Not Work - Brother PE770 Service Manual

Failure Investigation for Electronic Parts The touch panel does not work
Is the touch panel adjusted correctly?
Is the FPC of the touch panel
connected correctly to CN7 on the
main PCB and locked firmly?
Is the FFC connected correctly
between the main PCB (CN5) and
the motor PCB (CN1)? Are both
connector locks applied correctly?
Is the FFC
to the card PCB (CN1) free from breakage?
Is the resistance between pins 2 & 4,
and 1 & 3 of the touch panel 200 -
900Ω, respectively?
5 - 6

The touch panel does not work.

Y
Y
Y
connecting the main PCB (CN5)
Y
Y
Change the main PCB assy.
and adjust the touch panel.
N
Adjust the touch panel correctly.
N
Connect it properly.
N
Connect it properly.
N
Replace the FFC.
N
Change the touch panel and
adjust it.