Wear Indicators, Checking

WARNING: This page is about a different car, the 2021 Audi S4 and 2021 Audi A4 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

The wear indicators on the brake rotor friction surface are positioned 120 degrees from each other.

The wear indicators -arrow- can be recognized by their different color.

Fig 1: Identifying Wear Indicator By Difference In Color To Rotor Surface Metal
Courtesy of AUDI OF AMERICA, LLC
On the front and back side of the brake rotor are three wear indicators.

Wear Indicator OK

Fig 2: Identifying OK Wear Indicator

Courtesy of AUDI OF AMERICA, LLC

Burned-Out Wear Indicator, Example 1

Fig 3: Identifying Burned Out Wear Indicator

Courtesy of AUDI OF AMERICA, LLC

With increasing wear on the brake rotor, a dark burned-out recess develops on the wear indicators.
Even if only one of the six indicators is completely burned out, the ceramic brake rotor must be replaced.

Burned-Out Wear Indicator, Example 2

Fig 4: Identifying Burned Out Wear Indicator

Courtesy of AUDI OF AMERICA, LLC

With increasing wear on the brake rotor, a dark burned-out recess develops on the wear indicators.
Even if only one of the six indicators is completely burned out, the ceramic brake rotor must be replaced.

CAUTION:

Risk of accident due to insufficient braking action on worn ceramic brake rotors.

Reusing ceramic brake rotors that have reached the wear limit is not permitted.

- Immediately replace the ceramic brake rotors once they have reached one of the wear limits defined below.

CAUTION:

Risk of accident due to uneven braking.

- If a brake rotor is damaged or worn, check the other brake rotors for damage and wear.