Fujitsu AU A36LCLU Series Service Instruction page 61

Trouble shooting 17
OUTDOOR UNIT Error Method:
Compressor Start-up Error
Detective Actuators:
Outdoor Unit Inverter PCB
Forecast of Cause :
1. Connection failure
Check Point 1 : Check connections condition in control unit
Check if the terminal connection is loose.
Check if connector is removed.
Check if connector is erroneous connection.
Check if cable is open.
>> Upon correcting the removed connector or mis-wiring, reset the power.
OK OK
Check Point 2 : Check Compressor
Compressor check is refer to SERVICE PARTS INFORMATION 2.
>> If it is abnormal, replace compressor.
OK OK
Check Point 3 : Replace Inverter PCB
If Check Point 1, 2 do not improve the symptom, replace Inverter PCB.
Indicate or Display:
Refer to error code table.
Detective details:
Start indication goes from Main PCB to Inverter PCB.
But, if the compressor does not start for the below cause,
each treatments are done.
15 seconds after the above failures (
After 6 times of the above retries (Both and are counted as "1 time"),
3 minutes ST behavior is done. And the result of the above
treatment (
After the above sequence (
if it does not start, it stops permanently.
2. Inverter PCB failure
02-20
Cause Treatment
Over current Decrease start voltage
Start failure Increase target current amplitude
) is back to the default.
~ ) repeats 10 times (Total 60 times),
3. Compressor failure
or ), it is retried.