I've just had the same problem with my A4. Sorted by my local independent garage today for a reasonable £169. They also mentioned that should it happen again (unlikely) to get the sensor replaced sooner rather than later, as apparently the failure of the sensor results in the ABS system being deployed to compensate, which can only be done a set number of times before ABS components will need replacing.
Seems exactly my case. My approved used audi q7 plat 65, bought in June 2020 , has brake servo fault and start/stop fault in July (roughly 4 weeks after purchase ). I was hold to wait for 4 weeks to get appointment for repairing, during the first 3 weeks, I drove roughly 300 miles, and then there is red indication saying “brake fault- park safely” instead of the previous two yellow fault. Today I send it to nearest audi dealership, and was told it will cost £3500 to replace brake servo sensor and ABS module as well.
The car is in a two years warranty as approved used audi, So hope it is just a show bill and will be fully covered by warranty. I will check it tomorrow morning.
Brake servo restricted
in Audi A4 (B9) Forum
Posted
Seems exactly my case. My approved used audi q7 plat 65, bought in June 2020 , has brake servo fault and start/stop fault in July (roughly 4 weeks after purchase ). I was hold to wait for 4 weeks to get appointment for repairing, during the first 3 weeks, I drove roughly 300 miles, and then there is red indication saying “brake fault- park safely” instead of the previous two yellow fault. Today I send it to nearest audi dealership, and was told it will cost £3500 to replace brake servo sensor and ABS module as well.
The car is in a two years warranty as approved used audi, So hope it is just a show bill and will be fully covered by warranty. I will check it tomorrow morning.