2009 Audi A3 1.4tfsi Steering Angle Sensor Fault
 

Hi guys new to this site, so hope this sounds right!


Car had a wire broken in drivers door to pillar, fixed that issue and set-up windows, locking, etc
NOW.. when car is started amber steering light displayed in dash, after 2-5minutes airbag light comes on.

Done a code scan and these are the results..
"Brake Electroncis" code 00778 Steering angle sensor no comms.
"Diagnostic Data Interface" 00778 Steering angle sensor no comms. 00470 Combination comfort data bus single wire open circuit.
"Steering assist" 00778 Steering angle sensor no comms.

I fitted a new Steering angle sensor, made no difference what so ever, I have tested can-bus from interface and at steering wheel module.
I'm unsure what max voltage-min voltages I should be getting, I don't usually work on these make cars so any help thoughts would be greatly appreciated. I don't have pin outs or wiring diagrams for these cars.

Which wire was broken?
How did you repair it?
What did you use?
Did you disturb other wires in the process of the fix? That area is fragile.
Re-scan with door open/ half open/ closed.
Disconnect door harness from pillar and scan.
Check all fuses for safe measure.

I would re-check the repair and other wires in that location to start.

-Cheers

Thanks for your reply.
I fitted a new door loom, from the pillar out through the door.
I did disconnect and re-scan, same codes waited there. I'm guessing that issue is fixed when its waiting there??

Had a good look at the car today, I fitted a new steering angle sensor (In behind clock spring). but i'm still getting 00778 No signal/No comms with steering angle sensor. I have a scope and I've tested the can-bus wires going into the steering wheel electronics module. (the steering angle sensor, ignition switch and clock-spring all connect into this module) 4 can-bus wires 2 of these are signalling and switching as per how I saw can-bus operate. the 2 other wires and switching and signalling so fast even the scope can't keep with them. i'm thinking theres a fault in the steering wheel electronics module. any thoughts?
thanks for your advice

Did you get the issue sorted?

In my opinion your guess pointing to the steering wheel electronics module being faulty is where i would lean towards. Diving in further will get technical and i don't think i can assist without reviewing wiring diagrams and can signals, voltages and so on. However if and when you find the fix i would like to hear back.

If you have vag-com you can check in the measure blocks the status of each can-bus system and what is online or offline. I believe it may be able to show you an extra "clue" as to what is, is not, full, or partially talking and status. Don't remember exactly but using the advanced measure blocks just scroll through to find what measure blocks the info is located on. Switch to the regular blocks and see whats there. Sorry this is all kind of vague, but maybe it can help.