Just scanned the AWD on VCDS lite and came up with 00526 - Brake Light Switch (F): Implausible Signal. Looking at the possible symptoms it doesn't sound like it should and yes, I have Brake lights when pedal depressed.
Would this prevent the Haldex from working on my 1999 Audi S3?
I've driven the car and when I tried to come up the driveway on a small patch of ice (the rear wheels were on snow) and it sounded as though the front passenger side diff was grinding (maybe transfer box). The car refused to go up the drive unless I rolled back and then got traction on the fronts to get me over it.. SHould the rear wheels have "activated to help me up?
Note the driveway is not steep by any stretch of the imagination, it's as steep as a stepped curb, roughly 5 degrees I would imagine for about 2-3 feet then level.