connellync@gmail.com

Hi all, my 2003 six speed C5 Allroad is showing the “Brake Light” warning and beeping every time I press the brake pedal. Sometimes, the tail light warning comes on instead of the brake light warning.

My first step was to replace a taillight that was actually out. After doing that, the problem persisted, and a few days later my dash also showed the common three indicators associated with a stoplight switch failure: ABS, ESP, and suspension compressor indicators. The three indicators came on whenever I turned the exterior lights on (beginning with one click to the right).

So, I replaced the stoplight switch with a new Duralast RB492. This did not change anything.

Then, I realized one filament in one front inner turn signal was out. So, I replaced that too, and still nothing changed.

Finally, I replaced the other working tail light and both outside rear brake lights. This only stopped the ABS/ESP/compressor indicator problem.

Any ideas what to try next?

boostit

My 2001 Allroad C5 also has a rear light issue - although mine sounds a bit different.

Back in 2021 I had the "brake light" error pop up on the console digital display. Investigated and found the 3rd brake light above the rear hatch not working. Replaced that part (P/N 4B9-945-097-A) and all seemed well.

Now - "brake light" error came on in digital display though not a solid error. The reverse LED lamps come on when the headlights are turned on even when the car is not in reverse. I haven't dug into it yet.

Reverse lamps are LED - which hasn't seemed to be an issue till now - just a data point and I don't think they are the source of the issue - or I would have had a problem sooner.

So - have you investigated your 3rd brake light above the hatch? Is it functioning properly?

boostit

So I just investigated my reverse lights always on bug in my 2001 C5 six-speed manual.

Turning on the ignition but no start in neutral - the reverse lights were ON. Didn't expect that. After running through tests it appears that the reverse switch was stuck on. After shifting into and out of reverse on the 6-speed the reverse lights are now acting as they should. Not on when they shouldn't be and on when they should be.

connellync@gmail.com

I took my car to a shop, and they replaced my LED brake lights with standard lights because the LEDs draw so little power that the car doesn’t recognize they are on.

They also replaced the emergency flasher switch. Not sure if that was necessary; they broke it while they were investigating so had to replace it after that.

AudiAllTheWay

The bulb out warning system operates on a defined electrical current range for all monitored bulb circuits. If incorrect wattage bulbs and especially LED bulbs are installed then there will be erroneous bulb out warnings on the dash.