Audi A8: Brake Pad Wear Indicator Light On? (Solution)

The brake pad wear indicator light is on, but the brake pads are not yet worn out.

Cause:
The brake pad wear indicator in the Audi A8 can be activated in two ways:
The warning for the front brake pads is triggered when there is no ground signal on pin 7 of the 32-pin connector on the dashboard module. If the normally intact ground connection within the brake pads is worn through, this ground signal will disappear.
The rear brake pads are monitored by the electronic parking brake control unit. This unit signals insufficient brake pad thickness via the powertrain CAN bus to the instrument cluster. If the brake pad thickness was incorrectly calibrated, a warning may be triggered even if the brake pads are sufficiently thick. When the vehicle battery is disconnected or the power supply (terminal 30) to the electronic parking brake control unit is interrupted, the information about the brake pad thickness is lost and needs to be recalibrated.


Solution:
If a brake pad warning light is illuminated, follow these steps:
1. Perform the initial adjustment of the brake pad thickness. If the brake pad warning still appears after this, inspect the brake pads on the rear axle and replace them if necessary.
2. Measure the voltage at pin 7 of the 32-pin connector on the control panel module. If the voltage is greater than 1 volt, the front brake pads and the wiring should be checked and, if necessary, replaced.