2003 A8 Cruise Control Problem
 

Does anyone have a clue what would cause this...If I start my A8 and set the cruise, it works fine. Until I step on my brake or use the "resume" or any other buttons on the stick. If I do, the cruise seems to just shut down and is almost impossible to reset. However, if I shut the cruise off with the switch, I can turn it back on and it sets just fine. In other words, shutting off the cruise using any method other than the switch disables it totally.

RE: 2003 A8 Cruise Control Problem
 

A8's have way too many systems to just speculate on what it could be, you have to pull the fault codes with a VAG COM or the dealer. It sounds like the brake light switch is malfunctioning, when they do it turns off the cruise control.

RE: 2003 A8 Cruise Control Problem
 

A8's have way too many systems period - this car is way over-engineered... to the point of uselessness. My car (03 w/35k mkiles) has been to the dealer 4 times since June for the same issue (among others) - Today I'm driving my kid's Sentra since my car died (again) in CT last week.... left it on the side of the road hoping someone steals the POS

I miss my 540

RE: 2003 A8 Cruise Control Problem
 

While I am not an electrcial engineer, I am a retired comptuer network engineer and am having trouble with the brake light switch idea and am leaning more toward a computer-type issue for this reason: My brake lights work fine and the system shuts down cruise not just when I turn it off with the brake. It also shuts cruise off if I use the "resume" or "Coast" function on the stick.