vinkodex.
Known fault

B8 platform: the actuator motor of the electric parking brake

Typically above 50,000 km. It does not show up on every car.

expensive

severity

above 50,000 km

mileage

3

sources

3 sources next to the write-up.

The fault

How you spot it

A small electric motor built into the rear brake calipers applies the parking brake. This is a known weak point of the B8 platform (A4 B8, A5 8T, Q5 8R, allroad B8): moisture and road salt get into the motor housing, the electronics corrode, and the gears seize. The symptom is a parking brake that will not apply or will not release, with a fault message.

Two things are worth knowing about it. First, the system is sensitive to voltage: a weak battery dropping below 12.2 V can trigger an intermittent parking brake fault on its own, especially in the cold. In that case it is not the brake that needs replacing. Second, servicing the rear brake requires putting the caliper into service mode with a diagnostic tool; forcing the piston back by hand destroys the actuator itself.

Which model

Who it affects

The card opens the generation, the engine or the transmission.

Generations and models

4 generations.

Checklist

B8 platform: the actuator motor of the electric parking brake

What you would check for this fault. Take it to the car.

Before you buy

Checklist

What you tick stays on this device only.

vinkodex.com · Before you buy it, see what can go wrong.

Sources

How we know

Information, not an expert opinion

We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.

  • A fault on the list does not mean the car you are looking at has it.
  • A fault missing from the list does not mean the model is fault-free. Write-ups are made model by model. Not all of them are done.
  • You decide whether to buy. This is no substitute for an inspection. That needs a workshop and a history check.
Details in the terms