Daikin vrv L5 fault code (INVERTER COMPRESSOR FAULT)

[Improver]

Hi folks I recently attended a job with a daikin vrv (reyq12wm1b I think) running on r410a with an L5 fault code which corresponds to an inverter compressor fault. I have carried out numerous tests but I have not confirmed that the compressor is faulty,
so far checked the phase ouputs from inv. p.c.b with phase checker and they were o.k, carried out load test of running compressor and they were in tolerance about 9 amps and carried out an insulation resistance test of comp windings and they were clear (about 40 mega ohms).

Is there something i'm missing here guys? What else can I do to confirm the comp is faulty?

[AbsoluteWDJ]

Maybe mains power issues? I would check outdoor isolator, circuit breaker and terminals on outdoor unit. Make sure they are tight enough and there are no signs of corrosion. I take it the compressor operates when your on-site and you discover no abnormalities?

[install monkey]

replace the compressor and inverter kit-as youll have to for a 12mth warranty, if the inverter is alarming on l5 inverter overcurrent,ur compressor is siezing- u can go into the settings to disable the inverter compressor

[VRVIII]

replace the compressor and inverter kit-as youll have to for a 12mth warranty
Why would you replace the inv PCB when the outputs are OK? Why do you think this would make a difference to warranty? I have never heard of inv PCB fault bring down a comp.

[install monkey]

a faulty compressor will put excesssive strain on the inverter kit, daikin recommend replacing both hence the 12mth warranty, even though the inverter pcb has ct circuit to detect overcurrent this only alarms at 125% of the current

[Improver]

Thanks for input guys,
yeah mains power and terminations are fine, when I reset the system it runs for a few mins then goes to fault, I have put the system in a certain mode so standard compressor runs. I think i'm gonna go ahead and replace p.c.b and compressor it's just I have not seen an overcurrent or a fault to earth on my meters to confirm it's defective. I would like confirmation before I go ahead and order a few grands worth of parts that's why I asked for your advice to see if i'm missing something but i'm more confident now in replacing them so thanks guys for your input.

[install monkey]

when u get ur compressor confirm the model number of the compressor corresponds to the original one as i had a panasonic urban and ordered replacement r407c compressor and got a r22 one

[Improver]

ok will do thanks