4. Troubleshooting
Method for fault diagnosis
SMGB0097 rev.0 - 07/2015
96
4.7
Method for fault diagnosis
Summary of checks for fault diagnosis
Is 22.1V in PIN1~PIN2,
15.6V in PIN3~PIN4, 15.8V
in PIN5~PIN6 of the I/O printed
circuit board (PCBd) connector
CN56 and CN57?
Is 230V supplied to
transformer (TF
1
) primary side?
Is 400V supplied to the unit?
Check the power
source switch
Is R phase or S phase
failure?
Is fuse broken?
Connector repair
Is 22.1V in PIN1~PIN2,
15.6V in PIN3~PIN4, 15.8V
in PIN5~PIN6 of the printed
circuit board for CPU (PCBc)
connector CN2A?
Are connector CN1, on the printed circuit board
for CPU (PCB
c
), connector CN21 on the I/O printed
circuit board (PCBd) and Printed Circuit Board for Display
and Operation (PCB
A
) correctly connected and
checked loose connection?
Is 20.4V in PIN1~PIN2, I/O printed
circuit board (PCB
d
) connector CN55?
Is there power source?
Is there power source?
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
Yes
No
Yes
No
Yes
Is there power source?
No
Yes
Wiring check.
Connector check
Wiring check.
Connector check
Wiring check.
Connector check
Replace transformer
Replace transformer
Replace fuse
Replace transformer
Wiring check.
Connector check
Replace transformer
Check printed circuit
board for CPU (PCBc),
and the I/O printed
circuit board (PCBd)