Trouble shooting
Si04-115
70
Service Diagnosis
5.5
Faulty Indoor Unit PCB
Remote
Controller
Display
∗
Indoor unit LED
Display
Method of
Malfunction
Detection
The proper program operation of the microcomputer is checked by the program.
Malfunction
Decision
Conditions
When the microcomputer program does not function properly.
Supposed
Causes
"
Microcomputer program is in abnormal condition due to an external factor.
∗
Noise.
∗
Momentary voltage drop.
∗
Momentary power failure, etc.
"
Faulty indoor unit PCB.
Troubleshooting
Turn on the power again.
Check the grounding. (earth)
NO
Replace the indoor unit PCB.
Provide proper grounding.
The malfunction may be
caused by an external factor,
rather than defective parts.
Locate the cause of the noise,
etc., and correct the situation.
Dose it reappear?
Is the grounding proper?
(R1948)
YES
YES
NO
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
