Looking for a bit of advice and perhaps share my issues and possibly help out someone else.
Having issues with a 508 rxh i bought as a project.
The issue: Engine will start run for 2 seconds and stop.
The story leading up to the problem: car was boght with minor crash damage by my friend. He replaced needed parts and got the car back on the road. He got some overheating faults and diagnosed a bad coolant pump, replaced with brand new unit.
Shortly after the rear diff failed due to no oil in it.
It was replaced together with the rear motor as a complete 2nd hand unit. After that the car drove for a few weeks without issues and one day just stopped while idling.
Now the trouble shooting so far.
The are no codes stored in engine ecu.
Hcu 1 had can faults and hcu 2 had alot or dc sc converter faults. Assuming that the converter was faulty a 2nd hand converter kit together with engine ecu, bsi, transponder and key was purchased and swapped out. Car still would not run. How ever the dc dc converter faults are gone.
Also, replaced battery fuse box on top of 12v battery, new agm 12v battery, BSM box in engine bay.
Current faults
HCU1:
U12C6 - Hybrid can control network. Lenght error or prohibited value of the frame from hybrid management ecu 1.
U1286 - Can Hybrid network. Lenght error or prohibited value of the frame from hybrid management ecu 1.
P1AC4 - drive train. Failure of the activation of
The electro motor sub assembly.
HCU2 :
P1664- hybrid control ecu 2. Engine torque information fault (security level 1)
Suspected electric motor so replaced it with the original one. As only the diff was faulty on it. Still the same.
Now all these faults would clear after a while but reappear while starting the car. And car will not run longer then few seconds. Engine fault: repair required on the dash.
While looking at live data from hcu 2 in “ internal combustion engine” section it reads that engine rpm is at 14k rpm and coolant temperature -40 engine status - invalid value. Im suspecting wiring but not sure where to look, inspected wiring connectors and parts of the loom focusing on twisted wires for can connections but so far no luck, all other modules seem to read engine parameters correctly.
The hcu 2 DC DC converter reads voltage coming from alternator when starting around 200v and sees rpms etc so seems like coms are ok to it. Traction battery has no faults. Fan is working correctly as well as coolant pumps.
Any advice would be appreciated.
Ive booked it in with local dealer but the only agreed to take me almost 5 weeks from now so want to make the best of time to work on this.
Thanks again
