Start/Stop Fault

Hi, Upgraded my B7 to a B9 (190) Avant. (great Black Friday Deal from a car dealer in Scotland)Anyway, there is a message on the DIS on every start up "Start/Stop Fault, Go to Workshop". Message is in White. Message disappears after about 5 secs.Car drives as normal (to me anyway) apart from the Start/Stop not working.And also the rear door mirrors takes 20mins!!! to de-mist.

Am using latest HEX-V2 cable, scan on VCDS reveals 2 faults:

2 Faults Found:
197149 - Generator U1052 00 [009] - No Communication [Break_Down_LIN_Communication_Alternator]
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 4
Fault Frequency: 1
Reset counter: 159
Mileage: 114425 km
Date: 2019.12.04
Time: 21:45:15

197175 - Control unit for battery monitoring
U1050 00 [009] - No Communication [Break_Down_LIN_Communication_Battery_Monitoring]
Confirmed - Tested Since Memory Clear Freeze Frame: Fault Status: 00000001
Fault Priority: 4
Fault Frequency: 1
Reset counter: 159
Mileage: 114425 km
Date: 2019.12.04
Time: 21:45:15

Does someone know what these fault codes mean? Does Generator mean "alternator"? Im thinking there could be a broken wire somewhere The dealer where I bought the car put a new battery in on the morning i picked up the car (said it was -6 deg C and the battery died) I cant find a BEM code anywhere on the battery (YUASA 9060 70Ah). Checked with Audi and the battery for my car should be 80Ah. Could this 10Ah difference make an ounce of difference to the "start/Stop fault"Also tried to code the battery thinking this will solve the Start/Stop fault, connected on UDS protocol. Following the Ross Tech youtube guide, I tried to first change the battery capacity, there is no drop down menu so I have to type in the new value of 70 Ah. However I get following error, "conditions not correct or request sequence error".So not sure where to go from hereI hope someone can suggest a route forward other than replacing the battery, and possibly Battery control moduleMany thanks in advance.


[EDIT]
Text formatting

Took the car to a Main dealer on Mon. After 3 hours, they couldn't figure out what was wrong and wanted another 3 hrs! To be fair they didn't charge me and they washed it!!

Booked into to DNA Auto Tech for diagnostic today, hopefully I know what is going on.
Will keep you posted

Get it fixed then disable it from the negative terminal .

https://www.vwaudiforum.co.uk/forum/s...t-the-easy-way

*** Update ***
Open circuit found in a wire between the Gateway controller 4M1907468C and the alternator. New wire between the alternator and the gateway removes the start/stop fault. Mechanic is trying to find the node, wiring diagram doesn't give location of node so tracing the wire back to the node means some of the carpet and most of the trim is being removed.

Attachment 36494

Attachment 36495

Attachment 36496

*** Update 2***

Right I really need your help on this one.
So today the Start/Stop Fault was fixed. Mechanic found a corroded node between the C and B pillar on the nearside. He repaired this node, and Start/Stop Fault gone from dashboard.
He found that area of the wiring loom was wet. After peeling back the trim between the B and A pillars on the nearside, he found this (See video)

https://youtu.be/Qc3x96YZoHU

Yes.... that is washer fluid pi$$ing out!! That pipe is a thin walled corrugated plastic thing taking washer fluid to the rear screen. The pipe is encased in the wiring loom. Somehow, the pipe has pin holes that allow water to be sprayed along the wiring loom. This moisture must have corroded the node leading to the Start/Stop Fault on the dash. For now, the damaged section of pipe will be replaced and everything put back so that I can drive my car. Cant help but think which other section is also affected though

My question,
#1
Do I go back to the (non-Audi) dealer that I bought car off, as they didnt tell me about the fault, clearly as the noded was corroded, they must have know about the fault on the dash and not told me until I picked up the car.

OR

#2
Do I go to Audi (David vs Goliath) and appeal to thier good will as car is only 3.5yrs old withc FSH and say obvious manufacturing defect and I need the entire length of pipe replaced (washer fluid reservoir to rear screen).

Appreciate your help in advance

Got the money back from the dealer where I bought the car. Happy days.
I have got used to the Stop/Start, dunno why people want to disable it.

Un-surprisingly, my Audi dealer hasn't responded, will continue to chase.

Firstly, well done on getting a refund, secondly can't play your video but I got the picture via your description.... I have a saloon with no wash wipe....
That is one difficult fault to find so well done to your auto elect.

What car have you now?



Side note for you with any future A4 B9, @ 3-4+ yrs old the battery will need looking at as it is a Flooded Lead Acid battery and not AGM type by std. This will give an array of crazy faults too... all related to Can bus errors modules etc as standing voltage drops below 12.4v.

Cheers noscream
yes that Auto elec is going to get repeat business from me.
Still got same car - now that everything works i plan to run it into the ground like my last A4 (B7).
thanks for the heads up re: the battery - will keep an eye out.

Hi All
Often 02252 gen error is the known issue with the alt gen wiring harness.
Known fault NOT a fault in alt or regulator or batt.

Thanks vwfaultfix,
when you say KNOWN fault, do you mean known by Audi/VW Group?