chris.sargent

Hi, this is my first time post so sorry if I'm missing a few bits.

(apologies if you've read this already but I had posted somewhere else too...)

I've recently changed the steering rack on my Brother's Audi A8 4.2 Quattro on a 2000 W plate.

After putting it all back together the ABS and ESP lights are on permanently - not too surprised because we changed the tie rod ends. Sent it to get aligned an Audi specialist which they did, they then tried to reset / calibrate the steering angle sensor but were unable to do so.

They then did a live read and the VAG COM was showing the sensor was reading 360 degrees when the car was at straight ahead. So obviously during the course of hooking the steering column back on to the steering rack.

They then took the steering wheel off, moved the steering angle sensor back to zero and refitted the steering wheel.

Again they came to reset and recalibrate it but still the steering angle sensor won't take it. The garage is saying they've tried a few different codes to login, including the 40168 one but that the sensor will just not recalibrate. From what I can understand, the sensor is still reading it's angle correctly when in the live mode.

I have a few questions:

1. Is it possible to cause damage to the sensor by turning it too many times? (Because whilst refilling and bleeding the rack we had to turn from lock to lock several times and if the sensor was already at 360 degrees we may well have turned it beyond its limits). At the moment I don't see how this can be - it's an optical sensor and should therefore just keep turning until it's back around again no? - like an optical crank / cam angle sensor?

2. Does the car need to be driven in a straight line after the sensor's been put on correctly for it to 'reset' itself, then a calibration carried out.

3. Does the steering need to be turned from full left to full right to 'reset' the sensor before re-calibrating

4. Is there any other reason why it won't re-calibrate or any other steps that should be taken, other than those described in the wiki for recalibrating it.

5. Are these things partuclarly sensitive to being attempted to 'reset / recalibrate' them whilst they're off-centre?

The garage is convinced the sensor must be faulty but something just tells me they might be missing something?

Thanks for your help!

Chris

Uwe@Ross-Tech.com

Please post scan data from the ABS so we can see exactly what control module it has.

-Uwe-

chris.sargent

Hi Uwe,

Thanks for your reply. I don't have access to it at the moment as it's with an independent garage. However, we have sourced a replacement part from another car. We will fit this today / tomorrow and if we're still having issues I will most definitely ask them to provide me with the full output.

Thanks for you help!

Chris