Had same issue. Fixed myself by taking rear bench out . Taking sensors out and reconecting all plugs . Quattro has 2 senders on each side.
Also there is TBS in this . Just google
Hi all
New to this forum
Ive got A6 C6 3.0tdi v6 le mans in dytona grey pearl . Had the car for 2 years with no poblems so far, 119k on the clock . All original MMI 2g with bose on board plus sport suspention, 19" wheels