Malfunction (Parts) Check Method - IVT AE-X12GR-N Service Manual

AEX12GRN

[6] MALFUNCTION (PARTS) CHECK METHOD

1. Procedure for determining defective outdoor unit IPM/compressor
The following flow chart shows a procedure for locating the cause of a malfunction when the compressor does not start up and a DC overcurrent indi-
cation error occurs.
Connect power cord
to AC outlet.
Using remote control,
operate air conditioner
so that compressor
starts.
After about
20 seconds
Is there 230 VAC NO
between (1) and (N)
on outdoor unit PCB?
YES
NO
Is LED1 on outdoor
unit flashing?
YES
Compressor starts up.
Immediately
after startup
YES
Does LED1 indicate
DC overcurrent error?
NO
YES
Does LED1 indicate
rotation error?
NO
Normal
Check inter-unit wiring.
Check indoor unit PWB.
No
(unlit)
Does LED1 remain lit?
Is there 320 VDC between
pins IPM (31) and (35)?
YES
Serial signal error.
Check inter-unit wiring.
Check indoor and
outdoor unit PWBs.
Replace outdoor unit Replace outdoor unit PWB.
PWB.
Check compressor.
2/3-way valve closed.
Refrigerant shortage.
Replace expansion valve.
Outdoor unit PWB.
YES
15/5 V display section.
Voltage OK.
NO
Replace outdoor unit PWB.
Check posistor (PTC1)
(about 40
Check IPM.
Check fan motor.
Check outdoor unit PCB.
NO
Check wiring.
Check PAM IGBT (Q5).
YES
NO
+13 V, +15 V on PWB. Disconnect expansion
valve connector.
YES
YES
OK
Replace outdoor unit
NO
Replace compressor.
3 – 8
at 25 ).
NO
Replace outdoor unit PWB.
+13 V on PWB.
End.