Audi A4 tick / scratching noise, parking brake fault

[erikdude27]

So I picked up my 2011 Audi A4 Avant last week, and it's been an extremely good car. The car has followed service intervals, and has current gone about 86,000 km ≈ 53,000 miles.

The other day, I got a warning message on the center driver display. However, the message disappeared as fast as it came and I was unable to read what it said. I drove home, but noticed something was up with what appears to be the brakes.

Now, the problem comes and goes a lot, but it's almost certainly there every time I drive. What happens is that I occasionally hear a kind of tick in the wheels, and I can feel almost like a gentle poke on the pedal. When I brake (lightly seems to provoke it the most) it makes a scratching noice like "Brrrhmmm" and I can feel it in the brake pedal. The sensation is almost like a reduced ABS experience.

Often at the same time of driving (not exactly the scratch moment), but not necessarily - I get a warning message that reads "parking brake malfunction", followed by the stability system and ABS disabling.

These come and go, and sometimes I'm able to drive for an hour without any warning.

I may also add that the tick when driving normally is often followed by a slight "hiccup" in the car that you can feel. Almost like a little tap on the brakes

Never the less, I appreciate any tips or help with this at all! Thanks in advance!

Best Regards, Erik

[bluefox280]

The signs are pretty obvious with the warning massage and the "poke" of the brake pedal - you need to have the electronic parking brake system looked at.
Have access to a VAG-COM / VCDS? If so, scan the vehicle to determine what the current fault(s) are.

- Erik

[erikdude27]

The signs are pretty obvious with the warning massage and the "poke" of the brake pedal - you need to have the electronic parking brake system looked at.
Have access to a VAG-COM / VCDS? If so, scan the vehicle to determine what the current fault(s) are.

- Erik

I've found the cause at the Audi dealership. It's an RPM sensor in the ABS system that was worn out and has been wearing out the wheel bearings as a result. The sensor has to be replaced, and most likely the bearings as well.