Garages avoiding my Body Control Module fault (U0140) - affecting Start Stop

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T6 Transporter Stop/Start FIX, fault code 02252… Front crank seal and flywheel replaced.​

 
I have the same problem and I want to change the LIN wire from the alternator plug to the battery.
The yellow/green LIN wire that goes from the alternator...does it go directly to the battery minus terminal?
or does it go through the on-board computer (ECU) and then to the battery?
does anyone have a diagram with the LIN wire from the alternator ... the complete route?

thank you!
 
Finally got mine fixed after 3 different garages too lazy to investigate properly, Advised by the guy who had the patience AND know how that if it wasn't fixed it would put an undue strain on the smart alternator.
All fixed now, broken in 3 places, very thin wire used by VW which is unsuitably thin for where it is situated because of constant heat cold cycles and ingress of water..
Repaired with thicker gauge wire and heat shrink to protect it.
 
Finally got mine fixed after 3 different garages too lazy to investigate properly, Advised by the guy who had the patience AND know how that if it wasn't fixed it would put an undue strain on the smart alternator.
All fixed now, broken in 3 places, very thin wire used by VW which is unsuitably thin for where it is situated because of constant heat cold cycles and ingress of water..
Repaired with thicker gauge wire and heat shrink to protect it.
Who did you get to fix it for you @RichP ?
 
Just to add to this in case anyone is troubleshooting something similar:

I had no symptoms except for a dodgy start every now and then. Van drove fine with no warning lights.

On VCDS scan had some random codes including BCM, airbag and battery.

I replaced the battery with the higher 80ah which didn’t make a difference.

I got in touch with a mobile auto electrician who knew about this fault. He ended up finding two breaks in the green wire which he cut out and replaced and now all the codes have gone!

Happy to have this fixed and even happier I’ve now found a reliable and professional car electrician!

For all those in London, check out Totally Mobile Auto Electricians.

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I still have this issue. Tried the lin wire with my mechanic, still persist. Anyone know a reliable auto electrician in and around Brighton area?

Could the negative battery terminal cause this stop start error?
 
Tried the lin wire with my mechanic, still persist.
I had 3 mechanics saying they checked but only checked what was easy, The guy who actually sorted it checked ALL of the lin wire and had to take out the starter motor for access to fix it.
There are mechanics that say they know what they are doing, and a lot fewer that actually know what they are doing.
 
Yeah I know, that's the issue. Trying to find a decent trusty mechanic / auto electrician that knows their stuff.
 
I fix loads of these. Usual issue is water ingress sometimes coupled with ham fisted construction at factory or impact damage.

Here's one I did this week. Same symptoms: S/S error on dash, comms error code with no power output from alternator.

Cut out the bad and replace with a good length plus add extra protection from moisture and physical damage.

View attachment 186959
Hey mate.

Could you have a look at this photo and tell me if this could be causing the stop start error?

There's a very small part where the outer casing has split and exposed the internal wiring

If so what wiring do I need to fix this?

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A brilliant post this one ! I had exactly this problem a while ago and even after telling the 'good' mechanic what T6 forum advised, he said I had to change the alternator. So £500+ later still same issue then he looked at the wires and guess what !!
Alas, recently started having problems with battery not holding charge. Had to get a new battery ( be warned not a simple task of replacing BUT you must get reprogrammed even if like for like) but Halfords garage did great job and not Start/Stop perfect!!
 
Great to hear. Any chance of some more photos to pin point the exact cable loom at fault?
 
Top marks !! There's been too many reports for this particular issue/fault and VW should be taking the lead and issuing a FOC fix. It's as a result of bad design/workmanship and hence should qualify for a free fix. Alas, I doubt this will ever happen
 
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