Brake Light PROBLEMS, need help please.

[AudiA6]

I recetly purchased a 1996 GT 5-speed.

After having it about a month I walk out of the store and notice that my brake lights are on (all three of them). Well I make it home without anyone ramming into me.

Well I start to trouble shoot it. I check all the fuses and nothing is blown. So I go to Advance Auto and get a new brake light swtich and replace that. Still no help.

I then notice that I don't have any turn signals either. I go back to Advance and get the entire switch assembly that's located in the colum and replace that as well. Still no help. So i return to Advance yet again and purchase the 5 pin relay and replace the yellow one under my dash and still no help. No turn signals and my brake lights are still stuck on.

Any suggestions?

Any and all help would be greatly appreciated.

Thanks,
Anthony

 

[wmburns]

Confirm that the high mounted 3rd brake light is also on. If so, the 3rd brake light bypasses the multi-function switch. Therefore, the only logical place for the failure is the brake pedal switch itself.

There are no relays between the fuse box and the 3rd brake light. Power goes DIRECTLY through the brake pedal switch. Replace the switch and you will be good to go.

 

[AudiA6]

Thank you for the suggestion but that's the very first thing I replaced. The part I replaced was part number BWD S646 (V09261). I replaced it the same way it came out. Is there a special way to install/adjust?

Stoplight Switch by BWD - Part S646 - Advance Auto Parts

 

[AudiA6]

Where is the multi-function switch located. That's the only thing I haven't replaced yet.

BTW, yes the third brake light is ono as well.

 

[wmburns]

The multi-function switch is the "thing" in the steering column with the turn signal handle sticking out of it. I assumed that it has been replaced.

If you want to double check this is not the multi-function switch, disconnect the C288 connector under steering column. If the 3rd brake light is still on, it has to be aheard of the multi-function switch.

Also disconnect the electrical connect to the brake light switch. This should make the brake lights go out.

If you look at the wiring diagram, there is no other logical place for the failure to have occured and match your symptoms. The switch must be out of adjustment such that the pedal has not fully returned and is pressing on the switch.

Perhaps there is something between the switch and the pedal or the switch is not installed correctly.

Try pulling up on the brake pedal. Is the Master cylinder and the rest of the brakes working OK? Are the ABS brakes working OK? No warning lights and such?

The only other logical possibility is there is a short in the wiring harness. But it would have to be a real long shot such that it bypasses the brake switch and nothing else.

 

[AudiA6]

Ok I disconnected both the brake light switch and the c288 connector near the colum and the 3rd brake light is still on?

And yes I installed a new multi-function switch.

if you'd like give me a number and I can call you and/or call me

nine one zero, nine 9 0 , four four 7 nine

Thanks,
Anthony

 

[wmburns]

Any recent work?

Pull the fuses one at a time. There are two fuse panels (one in the engine bay, the other under the cluster). Start first with the I/P panel #9. Post the fuse that makes the lights go out.

Are you aware there are two brake pedal switches? One is for the lights the other for the curse control.

What are the wire colors on the brake switch replaced?

The brake light switch is LG/R and R/LG.

The brake pressure switch (backup cruise control) is LG/R and O.

Also, how many terminals on the switch? Possible to have installed backwards?

 

[AudiA6]

The fuse that turns the lights off is in slot #9

This is the brake switch that I replaced.

 

[wmburns]

Take the terminals off of the switch and measure the Ohms through the switch. If low, the switch is in the "on" possition. This could be because of a defective switch, incorrect installation, brake pedal out of adjustment (not fully retracted).

Possible the wrong switch installed. The cruise control switch is normally closed where as the brake switch is normally open.

You did not answer all of my questions from the previous post.

 

[AudiA6]

Thank you for all your help thus far it's greatly appreciated.
Sorry for the delay in my response but I was out of town.

What are the wire colors on the brake switch replaced? Light green with a red strip and Red with a light green strip

The brake light switch is LG/R and R/LG. ^

The brake pressure switch (backup cruise control) is LG/R and O.

Also, how many terminals on the switch? Possible to have installed backwards?
Two terminals on the switch and impossble to have installed backwards as the connector is a factory plug and will only fit one way.

Here's what I know for sure so far.

Replaced the Multi-function switch
Replaced the brake light switch with the light green wire red strip/red wire light green strip
Fuse #9 when pulled turns the brake lights off.
with fuse #9 in and with connention 288 unplugged the the only light still on is the thrid brake light


NEW: Airbag light on dash is now on. Would this have anything to do with my issue?

Again thank you so much for all your help.

 

[wmburns]

As the 3rd brake light bypasses the multi-function switch, the only logical place for this problem to be is in the brake switch itself. What are the results of the ohm test?

Optionally, pull one of the wires from the brake switch, does this make them go out? If it does, the brake switch must be defective, installed incorrectly, or the brake pedal is out of position.

 

[AudiA6]

Thanks I will go check now and post the results of pulling one wire.

As the 3rd brake light bypasses the multi-function switch, the only logical place for this problem to be is in the brake switch itself. What are the results of the ohm test?

Optionally, pull one of the wires from the brake switch, does this make them go out? If it does, the brake switch must be defective, installed incorrectly, or the brake pedal is out of position.

 

[AudiA6]

Both wires on the brake switch is reading 12 volts.

 

[wmburns]

12 volts on both brake terminals = problem

The fact that both terminals on the brake switch test for 12 Volts PROVES that the brake light switch has a problem.

Otherwise, only one side would test for 12 volts. The other side would test for 12 volts only when the pedal is pressed.

Double check your work. There is someting preventing the switch from returning to the correct position or the pedal is not in the correct location.

Orrrrrr you have the wrong switch. If this were my car, I would disconnect both terminals and test the switch for continuity (low resistance).

 

[AudiA6]

Both side of the factory plug WITH OUT the brake switch plugged in to it were reading 12 volts.

 

[wmburns]

I am out of the office at the moment and do not have access to the 1996 MY wiring diagrams. I do have access to 2002 MY. Unfortunately there are differences that make using the later model diagrams a bad idea.

I am assuming that the multi-function switch has been replaced. I am also assuming that the brake lights STAY on even with the brake switch disconnected.

To have 12 volts on the back side of the brake switch indicates there is feed back some where. Further, since the brake lights go out when fuse #9 is pulled, we know the feed back must be in the #9 circuit.

The fact that the 3rd brake light stays on with connector c288 (to the multi-function sw) removed indicates that the problem is before the multi-function switch.

Confirm what other work has been done to the car. Any previous break-in attempts? Any colision damage?

Unless you have some other insight as to where to look, I am afraid this is going to require a lot of very detailed electrical trouble shooting.

 

[AudiA6]

I am out of the office at the moment and do not have access to the 1996 MY wiring diagrams. I do have access to 2002 MY. Unfortunately there are differences that make using the later model diagrams a bad idea.

I am assuming that the multi-function switch has been replaced. I am also assuming that the brake lights STAY on even with the brake switch disconnected. YES and YES

To have 12 volts on the back side of the brake switch indicates there is feed back some where. Further, since the brake lights go out when fuse #9 is pulled, we know the feed back must be in the #9 circuit.

The fact that the 3rd brake light stays on with connector c288 (to the multi-function sw) removed indicates that the problem is before the multi-function switch.

Confirm what other work has been done to the car. Any previous break-in attempts? Any colision damage? To the best of my knowledge no break in attempts or colisons. The car fax came back clean when I purchased the car. What I have done since I got the car was replace the radiator, put sport lines springs, flowmaster 40 series cat back, tinted windows.

Unless you have some other insight as to where to look, I am afraid this is going to require a lot of very detailed electrical trouble shooting.

................Answered in your quote...............