My 2007 HOLDEN COMMODORE CALAIS-V SEDAN V6 AT Saloon wont start reads Error code U0100 after i jump started another car

[Pamela Smith]

My 2007 HOLDEN COMMODORE CALAIS-V SEDAN V6 AT Saloon wont start reads Error code U0100 on dianostic tool, it was after i jump started another car and now wont start been like that for a month, but it still has power going thru it? I have drained power out of car, charged battery, checked fuses, etc, It also now has contact dealer, low fuel, displayed on dash. It says that the code U0100 is the ECM and the OBDII reader isnt reading/communitcating with it is Engine Control Module eg ECU faulty, it also says Car maintenance/ fuel trim !, fuel system !, Overheating !, and Idling RPM !,Data not avaliable then the rest which is Battery Voltage 11.8 v, Engine Misfire and Engine Knocking are all thumbs up for good.

What is my problem help please

 

[bulkbogan]

Sounds like a fried/dead battery to me.

All those symptoms align with low battery voltage - might be enough to turn the lights on but none of the monitoring systems and sensors are getting the right voltage readings when feeding from the battery - and are throwing every money light they can.

If possible, check the voltage of the battery at terminals with a multimeter. 11.8v is too low, try charging again over a day or two (preferably trickle) and see if it can hold at least a steady 12.3v after resting off the charger. If no bueno, swap for another battery.

If the battery is testing fine, could be a myriad of things (bad ground, misplaced jump cables caused a short, ECU cooked etc) but that's way beyond my pay grade.

 

[gossie]

Did you leave your engine running whilst jumping?

 

[lout]

U0100 is a generic code for no communication with ecu
revisit your fuses and fusible links, sounds like your ecu is not powering up
were there any oops moments with jumper leads to wrong terminal
as you may have fried your ecu

 

[Fu Manchu]

Pretty easy to fry an ECU when jump starting another car.

 

[J_D 2.0]

Pretty easy to fry an ECU when jump starting another car.

Best to have the jumper leads with the little black box in the middle to help prevent voltage surges.

 

[Skylarking]

Pretty easy to fry an ECU when jump starting another car.

Yes it is easy because of poor design.

It’s not rocket science to protect the ECU and other rather expensive modules’ inputs from spikes and over voltage… Or if protecting multiple devices at $10 a pop is too costly, the manufacturer could put cheap as chips spike protection circuitry on the battery jump posts and make it idiot proof…

As to the OP’s problem, I’d load test the battery and check that the ECU is actually is getting the required voltage to boot up... If it is, it can’t be fuses, etc… it’ll be a something else but may be not the ECU…

Can bus communication faults can be caused by other modules on the bus so one really needs to see if the bus waveform good. If the bus waveform isn’t good, id be disconnecting modules on the bus one at a time until waveform looks good. If none of that helps, it could even be the bus terminating resistors…

Diagnose Dan (YouTube channel) goes into such diagnosis with multiple veg lies so is always worth a look at how he goes about solving some problems. A no start issue due to faulty door handle is just one can bus related foobar

Moral of the story, don’t be a nice guy and jump start other peoples cars. Help them by ringing roadside assistance for them (if their mobile phone battery is flat)

 

[lout]

Best to have the jumper leads with the little black box in the middle to help prevent voltage surges.

when my children first got their cars
i bought them a proper wheel brace, and surge and reverse polarity jumper cables and then showed them how to use them
you should see the reaction when young 20's girls whip out jumper leads and start someones car

 

[Pamela Smith]

Did you leave your engine running whilst jumping?

yup

 

[Skylarking]

Ah, just noticed you‘re a JC newbie so welcome to the forum…

Here’s just one DD video describing can bus issues that cause no speedo or gear position info being displayed in instrument cluster…

It may help you understand the diagnostics process a little more… There are more can look on on his channel, some related to no start issues, but can bus faults can cause all manner of troubles.

And here’s another..

And another…

But let’s not get too ahead of ourselves as it’s best to load test the battery to ensure it’s not simply old and dying and thatit’s just a coincidental thing that the battery plays funny buggers with you just after you did the jump start