A3 8L Mirror Defogger: No Function? (Solution)

Exterior mirror glass heating not functioning.

Affected vehicle identification numbers:
AUZZZ8LZWA000001 - 999999


Cause:
The control of the mirror heating was changed from "activation via the rear window heater button" to continuous heating without regulation, starting with model year '97. Additionally, process variations during manufacturing led to a failure of the heating element.

Solution:
Replace the exterior mirror glass.
Sure, here is the translation of the text from German to English:

"Note:"

The reflective surfaces are heated to an object temperature of up to +15°C, with automatic shut-off when the object temperature reaches +25°C. The tolerance is +/- 3°C.

Since there is no heating output at room temperature (approximately 20°C), it is essential to ensure that the object temperature is significantly below +12°C before performing a functional test. If necessary, the mirror surface should be cooled down using appropriate methods.