Help about Fujitsu General

Hello, colleagues :)

I am not a colleague per se, I'm an engineer by profession but I have a problem and I hope you will be able to help me. My air conditioner stopped working. When I turn it on, the internal unit seems to be working normally but when the air conditioner tries to switch on the compressor, it dispays an error. The LED Operation blinks 5 times and pauses, and the LED Timer blinks nonstop.

Can you help me with any service documentation, diagrams, instructions how to fix it? I hope I will be able to fix this myself with your help. I will really appreciate any help that you might provide :)

The air conditioner in question is Fujitsu General Invertor, Indoor unit - ASH13PSACW and Outdoor unit - AOH13PNAC.

I can´t find your exact model number (the 13 is throwing me off) but the fault code I have for a similar unit, with operation 5 flashes (0.5sec /5 sec off) and timer 0.1sec on/0.1sec off is Outdoor control unit abnormality. Could be anything really in the outdoor unit. Have a look and see if there are any more LEDS on the outdoor PCB.

You are engineer and error is: Outdoor unit current trip!
Of course, with this, I ask you to provide more answers than questions! ;-)

There is one LED on the outdoor PCB. After the compressor is switched on and displays an error this LED is lit permanently and fades 6 times, then is lit again, fades again 6 times and so on. During this time the voltage across the electrolytic capacitor is 320-330V. When I press the remote control unit TEST switch the outdoor fan starts rotating for about 4-5 seconds (longer than when I turn it on the usual way). During these 4-5 seconds the voltage across the posistor is 0V, i.e. maybe the power relay is ok.

It is probably compressor! Check his windings for equal resistance and for insulation strength!
Easiest way to check (without any specialized tools) if it is faulty compressor or PCB, is to disconnect compressor , and instead connect 3 light bulbs (100-200W) connected in star.

The resistance of all windings of the compressor is equal (15 ohm) and the insulation strength is good (measured with a multimeter). The three bulbs connected in star shine dimly and gradually get stronger. The outdoor fan works normally. What should I measure next? Could the problem be in the level of current protection because the light bulb load is significantly smaller? The problem didn't occur suddenly but gradually.

Compressor looks to be broken. For a start 15ohm is way to high, secondly the rest of the system seems to be OK (voltage to all the lights). I would have just used a multimeter to measure voltage, or a clamp meter for amps, or a good clamp meter that has frequency though.

So the compressor is drawing too much current, (motor fault or mechanically seizing) and you need a new compressor IMO.