For Anyone Doing the Brake Light Switch Replacement

[Rakshas]

Chances are if your OBC is telling you you have a "Brake Light Circuit Failure", but your brake lights are working just fine, your switch has gone bad.

There is a very good DIY on bimmerdiy.com
http://www.pelicanparts.com/BMW/tech...ake_Switch.htm
except for one major mistake.

DO NOT try to just yank the switch out of the bracket, or to break the housing for the switch. The plastic housing is actually far stronger than the tin metal bracket, and you will most likely(as I did) mangle your metal bracket. Instead, depress the brake pedal, slide the red collar forwards, and depress the tabs holding the switch in place. It comes out pretty easy, and you save yourself the hassle of bending the bracket back into the correct position.

[Tefal]

And if you leave the car running you will find it alot easier, as the servo aids you when you push the brake pedal down to pull the red collar out.

[RNeil]

depress the brake pedal

On my car, I had trouble pressing the pedal far enough by hand. I figured out you need to do this with the engine running so you get the power assist.

[Barbera328is]

thanks for the diy article

[2carsuprstar]

Chances are if your OBC is telling you you have a "Brake Light Circuit Failure", but your brake lights are working just fine, your switch has gone bad.



DO NOT try to just yank the switch out of the bracket, or to break the housing for the switch. The plastic housing is actually far stronger than the tin metal bracket, and you will most likely(as I did) mangle your metal bracket. Instead, depress the brake pedal, slide the red collar forwards, and depress the tabs holding the switch in place. It comes out pretty easy, and you save yourself the hassle of bending the bracket back into the correct position.

for me the best way was to take a pair of needle nose pliers, slide that "red collar" forward and use the pliers to twist it and the white rod until they break then break whatever pieces remain on that same side. the switch should slide out easy.

for me, the best way to get into position to see what u're doing is to slide and lean the seat back as far as it'll go, then get in it upside down and slide to the floorboard. even with the car on pressing down the pedal with my hand was a pain in the ass, so i just rested my head on it.

[Stevie328is]

Even easier. Unbolt the bracket that hold the sensor. There is just one bolt to remove.

[Blufire]

Even easier. Unbolt the bracket that hold the sensor. There is just one bolt to remove.

On my car, that one bolt is actually welded to the bracket, so that won't work for me.

[flyfishvt]

Rakshas, is that really your car? Love the color. If it is do you have anymore pics?

[Substream]

for me the best way was to take a pair of needle nose pliers, slide that "red collar" forward and use the pliers to twist it and the white rod until they break then break whatever pieces remain on that same side. the switch should slide out easy.

for me, the best way to get into position to see what u're doing is to slide and lean the seat back as far as it'll go, then get in it upside down and slide to the floorboard. even with the car on pressing down the pedal with my hand was a pain in the ass, so i just rested my head on it.

Exactly what I did, every word. haha worked like a charm.

[Automaticftp]

If people don't mind, I would add one thing: Do NOT push the white rod and red collar into the switch before installing it. I did, and it was a bear to get in--had to pull the white rod back out.

On the other hand, it is FIXED!

[Le Nitro]

I just did the switch replacement today...around 3ish...I followed the pelican DIY which was a f*cking dumb idea. I bent it until it broke, than pulled it out. Sure that worked. Than for the next hour I proceeded pushing the new one and it wouldnt snap in.

So verdict? The metal bracket that it sits in is not that strong and bent, I had to go underneath with pliers after I realized I bent it a tad bit, than a good amount of force and the new one popped in.

Edit: Holy shit that was what the OP wrote, I just read the last couple of posts lmao!

[brothersinc1]

Tried to get the switch out but no luck. So 1/2 hour later I said the heck with it and squished it with channel locks. Afterwards it came out real easy in about 2 seconds. Very satisfying too. Rob

[dcwright]

Tried to get the switch out but no luck. So 1/2 hour later I said the heck with it and squished it with channel locks. Afterwards it came out real easy in about 2 seconds. Very satisfying too. Rob

Same method I used. The housing breaks into small pieces and it just about falls out of the bracket.

I have a mirror that I lay down on the floorboard then I can see under the dash without having to stand on my head upside down in the driver or passenger seat.

[KoRny]

What should I do if I get the 'Brake Light Circuit' alert and my brake light also doesnt work? Its just my passenger side light, would it still be the switch?

[9T3 325iS]

Replace the bulb...brake light circuit means either an actual faulty circuit or a bulb failure.

[amarcilese]

for me the best way was to take a pair of needle nose pliers, slide that "red collar" forward and use the pliers to twist it and the white rod until they break then break whatever pieces remain on that same side. the switch should slide out easy.

for me, the best way to get into position to see what u're doing is to slide and lean the seat back as far as it'll go, then get in it upside down and slide to the floorboard. even with the car on pressing down the pedal with my hand was a pain in the ass, so i just rested my head on it.

This is too funny!! LOL. I just snapped the front bracket off on the switch and wiggled the switch right out! But in someway I wish I had read this post earlier..

[r33p04s]

thanks for posting this article a week late for me!!!

i ended up taking vice grips and cracking up the one that was no good and pulling it out then fighting with the brake pedal and the switch until i realized the red piece slides into the housing and clicks in for the new one ::

job done

PS
on my car the bolt was welded to the bracket so it wasnt coming out

[wahoomac]

this is a relatively easy task as long as you have patience & correct tools.

1. after removing underdash covers, locate the brake light switch which is directly in front of brake (you will see the red tubular sleeve)
I used a headlight (like a coal miner) that I use when duck hunting in dark...you will need light in the area working.
2. unhook the 4 pin connector by lifting the small black hinges on the side & pull off of brake switch
3. you must have someone sitting in the seat pushing the brake hard to give you room to work......if you start engine, it will help the brake to push farther.
4. do not yank switch out with pliers as you may bend the bracket.....I took a hand 6" saw while laying head underneath dash looking up on back with feet over seat in the farthest back position.
5. cut slowly through switch by bracket until it breaks....just make sure you don't cut through anything but the plastic switch...it will eventually loosen & break apart....pull it out of there
6. put new switch in the same way it was situated...(the rounded end down, square end up on the end where the 4 pin connector attaches)
make sure the white plunger & red tube sleeve are pulled all the way out.
7. it is extremely difficult to just push switch straight in......I found if you put switch in tilted a little to the side & then snap it sideways a little it will pop in.
8. reconnect the 4 pin connector
9. it took me about 3 hours

[r33p04s]

it's really easy once you get it out... I had to mangle the switch and snap the end off to get it out

i forget exactly how it went in but i facepalm'ed when I put the new one in because it made taking the old one out much easier

[Optical Toxin]

And if you leave the car running you will find it alot easier, as the servo aids you when you push the brake pedal down to pull the red collar out.

I know this is old but it's worth quoting. I replaced mine earlier this year and this trick would have helped a lot. It's hard to do this by yourself since the area is so tight. You can either get a good angle on depressing the brake pedal and have a hard time getting the switch off, or you get a great angle on the switch but no leverage to get the pedal down far enough. I ended up taking a big ass pair of pliers to the switch and crushing the part the is clipped into the bracket, then used some needle-nose pliers to cut it up more and pull it away.

Cliffs: Do what's quoted, makes things a lot easier.

[mjvanek]

I just did mine yesterday and ran into the same problem of not being able to remove the switch without breaking the locking tabs. One observation I made after I had finished the project was that the locking tabs cannot be depressed unless the switch plunger and the red sleeve around it are fully pulled out (Hint: Look at the new switch. The white plunger and red sleeve should be extended about 1/2 inch from the switch body. The plunger will adjust to the right position after it is installed and the brake pedal mechanism pushes it in as the brake is released). To do this you must pull both plunger and sleeve out together at the same time with the brake pedal push as far as it will go (and held there until the switch is removed). With the plunger and sleeve fully extended, the tabs should move easily one at a time using a small flathead screwdriver. Obviously I have no experience that this will ease the switch's removal, but it is the only way to do so without breaking the tabs. In the end the simplest solution might be to break the locking tabs using a small flat screwdriver levered between the tabs and the mounting bracket the switch is attached to. Hope this helps future brave souls from having a 30 minute job turn into a three hour nightmare. Good luck

[JDStrickland]

I just did mine yesterday and ran into the same problem of not being able to remove the switch without breaking the locking tabs. One observation I made after I had finished the project was that the locking tabs cannot be depressed unless the switch plunger and the red sleeve around it are fully pulled out (Hint: Look at the new switch. The white plunger and red sleeve should be extended about 1/2 inch from the switch body. The plunger will adjust to the right position after it is installed and the brake pedal mechanism pushes it in as the brake is released). To do this you must pull both plunger and sleeve out together at the same time with the brake pedal push as far as it will go (and held there until the switch is removed). With the plunger and sleeve fully extended, the tabs should move easily one at a time using a small flathead screwdriver. Obviously I have no experience that this will ease the switch's removal, but it is the only way to do so without breaking the tabs. In the end the simplest solution might be to break the locking tabs using a small flat screwdriver levered between the tabs and the mounting bracket the switch is attached to. Hope this helps future brave souls from having a 30 minute job turn into a three hour nightmare. Good luck

I did not know there was a DIY on this when I did mine (I didn't even know there was a forum on the interweb -- thank you Mr. Gore -- that we could come to), I took the switch out, opened it up and cleaned the contacts, put it back together, and reinstalled it. I do not remember anything about the job that was hard or required a destructive removal technique.

[shogun]

I took the switch out, opened it up and cleaned the contacts, put it back together, and reinstalled it. I do not remember anything about the job that was hard or required a destructive removal technique.

Looks like I have to do the same. Get the warning light. As I do not like to break something and like to repair as JDStrickland likes it too, I will try to get it out intact.
Looks like this is the solution, or does anyone have actual different/better experience?

One observation I made after I had finished the project was that the locking tabs cannot be depressed unless the switch plunger and the red sleeve around it are fully pulled out (Hint: Look at the new switch. The white plunger and red sleeve should be extended about 1/2 inch from the switch body. The plunger will adjust to the right position after it is installed and the brake pedal mechanism pushes it in as the brake is released). To do this you must pull both plunger and sleeve out together at the same time with the brake pedal push as far as it will go (and held there until the switch is removed). With the plunger and sleeve fully extended, the tabs should move easily one at a time using a small flathead screwdriver. Obviously I have no experience that this will ease the switch's removal, but it is the only way to do so without breaking the tabs.

This is an instruction for the E34/E32, but basically the same:

Depress the brake pedal and slide the red sleeve all the way out, keeping the brake pedal depressed. You may hear some clicking when it pulls the ratcheted white end post out to it's fully extended position, but it will stop at the end of its travel. Then pinch the two retainer clips together & pull the switch out of it's bracket. It may need some persuasion with a screwdriver to pry it out.

the pics might help http://www.nmia.com/~dgnrg/page_25.htm

[matlock328]

Just as easy to crush the old one to bits with some strongs grips, and if its like every other old plastic part in my car it will be brittle as hell and just disintergrate, like mine did. Getting the new one in was tricky, so I removed the bracket. BAD IDEA! getting the bolt back in the hole is tricky, especially hanging upside down, and depressing the switch on the brake pedal with one hand!

[monkey7037]

The nut is only welded on one side, u have to undo it from the other side to remove bracket, (which is the best way)
it is a pain to get to but I got in there with a 10mm socket and ratchet and had it off in 10 mins. No danger of bending the bracket, no need to headbut the brake pedal! And gives u loads of room to fit new switch