devinsixtyseven

2004 A6, 2.7T, BEL, 6spd manual.

This part fouled a while back, but the intermittent nature of the warnings I was seeing made me think it was a damaged wire or loose connection (huge pain to diagnose), plus a faulty ABS unit (300+ rebuild, 1000+ replace with new).

The brake light switch is a ten dollar part, it's easy to replace, and when it fails, it can produce taillight, brake light, and ABS warnings on the console, prevent the ABS/traction control unit from operating, and make it appear that perfectly good dual-filament bulbs have burnt out (brake and tail are in the same bulb in a C5 A6). These symptoms may be intermittent; ABS system will be unavailable one day, working the next. The red BRAKE indicator may flash, with a warning beep, or the console may signal a blown taillight or brake lamp (or both)...this combination of symptoms, in my case, was all the result of a worn brake switch at about 140K miles.

The only way to differentiate between a blown bulb, faulty ABS unit, and damaged wiring harness is read the codes with VCDS...only one code in my case, brake light switch, nothing else.

The switch likely started going bad around 105K miles, but I didn't own a VAG-COM yet, and it was very intermittent...one day the ABS/traction system might go down, then it would be fine for a month.

On to the repair...photos to come.

Just Me

Looking forward to the photos since i've never done one, but anticipate the honor some day.

Grant

devinsixtyseven

Pop the console cover off the back of the steering wheel.

http://www.imagebam.com/image/0a0c5b255057868

You'll see this...there are two 8mm bolts, one to either side of the steering column.

http://www.imagebam.com/image/25e83f255057865

This is taken after the lower console was removed.

http://www.imagebam.com/image/f1ab61255057862

There is a third 8mm bolt under the fuse box cover. Use a small flathead screwdriver or equivalent to pop the cover loose, bolt is buried in the hole in the photo.

http://www.imagebam.com/image/d32f3d255057858

The last two 8mm bolts are at the bottom of the console, one on each side of the footwell. Carefully pull the lower console free, don't damage the wiring to the diagnostic port or the courtesy lamp. You may need a pair of needlenose pliers to free the courtesy lamp connectors from the bulb. The diagnostic port has a couple plastic clips and releases easily.

http://www.imagebam.com/image/83ca5d255057857

Here's the brake light switch. Release the plastic clips on the connector, turn the switch clockwise until it releases, then pull straight out. Reassemble everything and you're done.

http://www.imagebam.com/image/9bf8c5255057855

rk1.8t

I just replaced mine couple days ago. easy install, just need to be very careful when turning the switch to lock in and activate. it's pretty much a time shot otherwise if damaged then the switch is no good anymore.

my abs/esp light was on before and I thought it was something totally unrelated. since I changed the switch both lights have been off. Took a cop to pull me over and notify me I had no working brake lights to figure it out.