SIE-86
Troubleshooting
Service Diagnosis
63
5.7
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)
YES
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.
Does the same
LED indication appear
again?
Is the grounding proper?
(MF004)
NO
YES
NO
Si-86.book Page 63 Friday, June 23, 2000 10:26 AM