VZ Commodore - Wont start when hot, fan not on w/ idle, relays hot, fuel gauge error

[karwalski]

I was in the suburbs, every time I stopped at an intersection it got hot (fan was not coming on).. then I went into the shops, came out 20 minutes later, and they car would not start.. after about 30 minutes, of *something* cooling down car started fine, no errors...

More details on "would not start"
- No clicking in engine bay
- Engine start, Engine Computer, Fan 1 Relays in engine bay EXTREMELY hot! also ignition, blower, etc relays under dash
- Fuel gauge read empty, error came up "Fuel Gauge Error" then "Service Vehicle Soon" and the little SVS logo
- Onboard service menu gave me the fuel gauge percentage of "0/Error" and the error code menu gave me "00....001000"
- I tried taping the relays and swapping with the high beams relay, and testing each relay in the high beam location, each appeared to be ok

A couple of extra notes
- If I turn the air con on, one of the fans will come on which solves the getting warm while stationary issue (maybe not solves, but provides a get around)
- I tried to replicate the fault when cold by removing the relays I suspected of sticking, (engine start and engine computer) however it resulted in the car not starting, no click..... but I did not get the fuel gauge error
- I am thinking an electrical fault of some kind because the relays are getting red hot, (even discolouring) im a little worried they will catch on fire.
- My fuel guage works fine the rest of the time, so im thinking its showing as a fault either because its number "1" in the list of all the things wrong, or because the fuel gauge doesnt get power from the engine computer when this fault occurs.

Thanks in advance

[RiCeY]

Primary fan motor could be cooked and is drawing a heap of amps which would heat up wiring and relays.

Could also be a poor connection at the battery or earths resulting in high resistance.

[richardpalinkas]

I've got the same thing wrong except overheating. Fuel gauge stops working which immobilizes the car, have seen the 0010000 fault in dash too as I stated in another thread. Scan tool shows com bus error in PCM and requires new ecu. Sorry to say but sounds like your ecu, like mine, has got the craps. Next time it does it's problem, look at the coolant temp in the dash diagnostics. Bet it reads 215 degrees

[karwalski]

Primary fan motor could be cooked and is drawing a heap of amps which would heat up wiring and relays.

Could also be a poor connection at the battery or earths resulting in high resistance.

I will disconnect the fan at the plug and work back to see if its the problem. maybe i damaged ot when i had it out for the radiator swap. 6 month old battery with good connections at terminal. will check earth connection.

I've got the same thing wrong except overheating. Fuel gauge stops working which immobilizes the car, have seen the 0010000 fault in dash too as I stated in another thread. Scan tool shows com bus error in PCM and requires new ecu. Sorry to say but sounds like your ecu, like mine, has got the craps. Next time it does it's problem, look at the coolant temp in the dash diagnostics. Bet it reads 215.

Yes! 215 when its faulting. but under 90 when i last turned it off. only other time i seen the max reading was when there was only air left in the system cause the radiator leak.

Thanks for your answers.

[richardpalinkas]

So far from Holden $750 for me, but I'm going to the wreckers to source one

[morphix]

]I really dont want to have to replace the ecu. any idea what they cost? Trying to sell the car so i dont wanna spend alot or have the car with strange faults scaring away the buyers.

I recently had to replace my ECU as i was getting all sorts of errors, eg. Fuel Gauge Error, Remote Central Locking would lock the car on its own (even while in it!), Check Powertrain and SVS warning popping up on every second start, engine majorly misfiring to the point it would cut out completely amongst other things.

ECU was $1150 brand new, including programming from Holden, regardless where you source this from, it MUST be programmed, or atleast your BCM to be programmed otherwise you won't even be able to start the car or lock/unlock with remote key due to the security system not having the same codes as the ECU and they wont communicate properly.

[m1lky]

If you start it from cold will it idle once its warm?

Does it always turn over and start easy when cold?

[karwalski]

If you start it from cold will it idle once its warm?

Does it always turn over and start easy when cold?

starts and runs fine when cold. even runs fine when warm, unless the aircon is off. and still then only issue is a spike in temp while stationary. The hot relays are my major concern dont want them to catch on fire.

When this rain clears will try rule out the fan drawinv too much current

[karwalski]

Relays still get hot when both fans unplugged

[RiCeY]

Id be trying new relays to eliminate them as the issue.

[richardpalinkas]

I doubt relays would cause the dash to read erratic readings and imobilising the car thinking it has no fuel.

[RiCeY]

No they wouldnt but it doesnt mean theres only one issue with the car. Relays shouldnt get hot so replacing them may cure one issue then we move on to the next.