Brother PR655 Service Manual page 259

Failure Investigation for Electronic Parts
From the previous page
The power is not turned on.
From the previous page
Y
Does the machine function normally when the power
supply PCB unit is replaced with a reliable one?
N
Does the machine function normally when
the main PCB is replaced with a reliable one?
N
Does the machine function normally when the
panel PCB is replaced with a reliable one?
N
Y
To the next page
5 - 4
N
Change the power switch and
the lead wire assy:power.
Y
Change the power supply PCB
unit.
Y
Change the main PCB.
Y
Change the panel PCB.
N
Change the lead wire assy:
panel-main.