Brother PR655 Service Manual page 285

Failure Investigation for Electronic Parts
• Panel communication error.
• Communication timeout error.
• Data receiving command error.
• Communication error.
(Dialog message)
Is the panel lead properly connected to
connector CN5 on the panel PCB and
connector CN10 on the main PCB?
Is the resistance between each pin at both ends
1 or below when the panel-main lead is
removed from the panel PCB and the main PCB?
Does the machine function normally
when the panel PCB is replaced
with a reliable one?
Error message
Y
Y
N
Change the main PCB.
5 - 30
N
Connect them properly.
N
Change the lead wire assy:
panel-main.
Y
Change the panel PCB.