Q5 Steering angle not matched intermittent

[Stefan N]

Hi,

Few months ago someone tried to steal my Q5 and messed up the BCM - the car was completely dead.
It was then put on a flatbed truck and taken to a garage, where it had a new BCM, adapted coded etc.
All fixed, but then I left the car parked for 3 days and I got yellow steering wheel and ASP faults on the dash.
The same garage said that the fault is angle not matched intermittent and performed basic setting.
Fault disappeared and drove for weeks OK, but then left the car again for 3 days and guess what - yellow steering wheel again!
I'm really puzzled what could be happening during these 3 days of not driving the car?
This thing is reproducible every time - I drive the car, fault disappears, I then park it for more than 2 days and then throws the fault with the slightest movement of the steering wheel.
Could it be moisture, but then why is it so accurate, needing more than 2 days every time to throw the error?

Thanks

 

[NHN]

How olds the battery?

Get it tested.

 

[Stefan N]

This is a good point, thanks.
The battery is not new, perhaps 5+ years old, but isn't modern electronics equipped with regulators?
I don't know where the adaptation values for the angle sensor are stored (BCM?), but I would be surprised if this loses data so easily.
Unless it happens during cranking... I will measure it.

 

[NHN]

This happens with weak batteries tbh, given the weather, check this 1st then go from there.

 

[Stefan N]

I put a new battery and did this with auxiliary battery connected to the front to prevent modules from resetting.
Still the same yellow dash on the board.
I borrowed a cheap Bluetooth dongle and read 03110 and 00778 faults, which may be lost basic settings or intermittent connectors perhaps.
Also took the car to a garage and they said that there's a faulty level height sensor - not sure what this is, has it got anything with the adaptive suspension? Or is it for the headlight adjustment...
But in either case I don't know how this could be related to the yellow steering wheel lamp on the dash.
They said the angle cannot be reset if there's this fault for the level sensor.

 

[NHN]

Ideally a full scan is needed.

 

[Stefan N]

It turned out that it was the rear right level sensor, not all diagnostic cables were detecting it, but after replacing it all went fine.
Strange why a level sensor would trip steering faults, but it's great that it is now sorted.

Thank you all for your help.