I have an 03 A4 1.8 quattro and the brake light out is on and it is working fine. I have scanned the ecu with no problems found. Doe anyone have any suggestions.

Thanks

 

unplug that battery for 10 mins

 

Did disconnecting the battery solve your problem?

 

Just a though - perhaps you replaced a brake light that indicates a slightly different voltage potential which is causing the brake light failure warning lamp to light up? This has happened to me before.

You might want to try replacing the bulbs on both sides with the exact same type of bulb.