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Section
IV - 9
SM830082
4. Service procedures
(5) Symptoms and parts to inspect
1) Symptom: LCD on the remote controller does not display and remote controller does not
operate.
No
No
No
No
No
NoNo
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Start
Replace the
indoor unit PCB.
Repair the
remote
controller
wiring.
Has the indoor
unit PCB fuse blown?
Check and repair the
power breaker etc.
Replace the indoor unit’s
power transformer.
Is the 230-208 V AC
circuit shorted?
Replace or repair.
Replace the
indoor unit PCB.
Is there 230-208 V AC
between R and S of
the indoor PCB?
Is the LED (D80) on
the indoor unit PCB lit?
Is the primary
side of the indoor
power transformer
shorted?
Is there 230-208 V AC
between U1 and U2
of the terminal plate?
Are the connections
for the 4P connector
for the indoor unit’s
PCB power trans-
former good?
Is there 15 V AC
between 1 and 2
of the 4P connector
for the indoor unit’s
power transformer?
Miswiring of
power supply
wires and
indoor/outdoor
control lines
Correct the
connections
Replace the
indoor unit power
transformer.
Correct the
wiring. Remove the
socket connected to
the OC plug on the
PCB and connect to
the EMG plug instead.
2095_THS_I