Sudden cut out. Esc & Acc error - No crank - Nothing on diagnostics

[voltswagon]

Thanks when ignition turned off it goes back up to 11.8v
With ignition on the radiator engine fan is going full pelt. Stops with ignition removed.
Is this controlled by the ECU?

 

[voltswagon]

Had AA out again today. Tried a tow start and some other electricals came back to life like power steering & brakes but it wont let the engine start so he thinks it's ECU problem as no communications with the ECU and other things ok.

Tried to removed the ECU but this torques bolt is just spinning it holds themetal cage that keeps the ecu in place lol.
Any ideas? It's in with the main engine fuses under the battery position. The design gods must have been on holiday.



Gunna send it off to these guys, for testing.

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[Lukefx]

Hi @dopeytree did you get to the bottom of this?
I've got the same non crank issue although have full battery power.

 

[voltswagon]

Nope auto electrician said he agreed probably ECU as nothing from ECU on diagnostics but everything else talking ok.

He wanted me to take it to main VW in bridgwater which is a marshalls but they said they can't see it until end of March.
Just booked in with my local VW specialist who again can't fit it in until 20th March. Not sure if mechanics have all quit or places just busy or they dont want the ECU job.

Really it should be a pretty easy diagnostic to remove it & send off to be tested.

I might try the AA again and see if I can get them to remove the ECU for me.

How're you getting on with yours? Did it suddenly cut out too?

 

[Lukefx]

Nope auto electrician said he agreed probably ECU as nothing from ECU on diagnostics but everything else talking ok.

He wanted me to take it to main VW in bridgwater which is a marshalls but they said they can't see it until end of March.
Just booked in with my local VW specialist who again can't fit it in until 20th March. Not sure if mechanics have all quit or places just busy or they dont want the ECU job.

Really it should be a pretty easy diagnostic to remove it & send off to be tested.

I might try the AA again and see if I can get them to remove the ECU for me.

How're you getting on with yours? Did it suddenly cut out too?

I think they're just so busy and these days it takes a lot longer to get parts so everything takes longer.
And no, mine didn't suddenly cut out, it drover perfectly and then when I went to move it 2 minutes after turning off would crank at all.
Batter is good on mine and all fully charged now at home so no issues there.
I'm thinking starter motor as I've checked all the fuses and can hear the relay clicking.
Mechanic is hopefully here tomorrow.

 

[roadtripper]

I'm not sure if there is suitable access in a T6/6.1 but a useful trick if you have a jump pack and you can hear the solenoid physically clicking in is to apply the jump pack across the starter motor terminals - if you have a bad earth restricting current to the motor or a jammed motor this might give it the kick you need - I was reminded of this trick recently in unusual circumstances

It might also be worth considering if the pinion is stuck on the flywheel - a shock with a rubber mallet or gently rocking in gear might free that up.

 

[T6_FunBus]

My negative terminal wire is like this. I think this is the 'smart' linbus wires?
Wire exposed but still 'connected'. The blue thing is his probe.

View attachment 224932

Those two wires are always like that. That is the battery monitoring module, the yellow / green is the LIN wire that goes back to the BCM (and is also spliced into under the battery for the smart alternator). Those two wires can also break easy as it’s bent back and clipped to the shield at the side of the battery. I need to do mine at some point as there is an intermittent connection there.

That module won’t be causing your problem - you can unplug that connector and your van should still start, it would just disable stop start and throw a static error on no coms with the battery module.

 

[voltswagon]

Took the battery out and did a full charge. Had it fully disconnected for a week. Put battery back in to tow to local garage. They say it started up straight away. Took it for a test drive. All good.

Not sure I believe the didn't do anything but anyway it seems fixed. Notice it thinks cruise control is on the dash (doesnt have cruise control fitted). So appears 'fixed and drivable'. Best bit is no cost.

 

[roadtripper]

You've effectively done the full ECU restart by having the battery off the van for a bit. It's always worth trying that as the final step before having someone look at things if there are confusing electronic things going on. Initially it's likely to have a few issues as the ECUs start up in different orders but a short drive will generally resolve those.

 

[voltswagon]

Thanks good to know. It had been disconnected before but must need longer to reset.

Its been for a few drives now & still thinks cruise control is on, logo bottom of the dash (van doesnt have cruise control fitted but does have city braking radar).

Am going to remove the front radar (city braking only) and check wiring give it a clean and put back.

Will then book into VW for a proper check soon.

I have a copy of VCDS but it doesnt work any longer.