My 2004 TT S-line ECP light came on and the car would not excelerate. When I turned the car off I also noticed that the brake lights were stuck on. It eventually ran the battery down. I purchased a new brake light switch from the dealership and replaced it on my own. It fixed both issues. Apparently the brake switch causes the ECP light to trigger. The parts counter guy said the old parking switch design was bad and Audi redesigned it. The new part only cost $3.75, I assume because of all the quality issues related to it. On of the cheapest fixes I've ever had.

 

So glad to have found this thread. I've been having the same problems and was worried about the brake lights draining the battery. I will pick up this brake light switch and install myself. Any good resources out there for the install, or is it pretty self explanatory?

 

may have left my blinker on when I pulled into the spot. Went out cranked up the car, turned off the signal lights and poof the lights went off...?! Worked for me. Good luck.

 

Hi I woke up one morning ro find my Q7 brake lights on lighting up the street. When I looked into it there's a small push button switch in front of the brake pedal in which when you push the brake it relises the switch which turns the lights on, this had failed and a new one was a cheap and easy fix cost me £40 fitted hope this helps.