Si12-411A Troubleshooting
Service Diagnosis 171
5.3 Indoor Unit PCB Abnormality
Remote
Controller
Display
A1
Method of
Malfunction
Detection
Evaluation of zero-cross detection of power supply by indoor unit.
Malfunction
Decision
Conditions
When there is no zero-cross detection in approximately 10 continuous seconds.
Supposed
Causes
Faulty indoor unit PCB
Faulty connector connection
Troubleshooting
Note: Connector Nos. vary depending on models.
Control connector
Connector connection check
(note).
YES
Is it normal?
NO
Correct connections.
Replace PCBs.
(R1400)
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Model Type Connector No.
Wall Mounted Type 20 / 25 / 35 class Terminal strip~Control PCB
Wall Mounted Type 50 / 60 / 71 class Terminal strip~Control PCB
Duct Connected Type Terminal strip~Control PCB
Floor / Ceiling Suspended Dual Type S37
Floor Standing Type Control PCB : S7, S201, S203
Power Supply PCB : S8, S202, S204