I've had a TPMS error message 'Tyre System Malfunction' coming up on my 09 A6 Avant 2.0TDIe for some time. After a visit to the Audi dealer they told me they were unable to fix so contacted Audi for support. No further contact from them so I called them again, twice, and eventually got it booked in again. This time they told me they needed it for two days to really investigate in depth and get online support from Audi. When I checked on the second day they said there was a slow puncture in the O/S/R and this was why the error came up - the TPMS was doing its job. Keeping my emotions in check I patiently explained that if that was the case the message would be ‘OSR Underinflated' not 'Tyre System Malfunction' When I picked it up they said they had reset all the fault codes and it would now be OK if I got the puncture repaired. Switched on in the car park and guess what - 'Tyre System Malfunction' came up immediately.

My question is where do I go from here? If an Audi main dealer cannot find the fault who can? Is 3 days not enough time? Has anyone here had a similar experience with the TPMS and what was the fix please? I understood the ABS sensors were used for this function and there have been no ABS faults coming up so I guess it must be a control unit problem?