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Thu Mar 08, 2012 8:36 am

Hey folks I'm trying to figure out how to fix my brake light woes. They do come on but only with heavy pressure on the pedal. This is a 90 automatic Carat. Twice I've had cars drive up next to me saying my brake lights are not working. I feel it in the trigger on the pedal but can't seem to figure out how it works. Its way up there behind the fire wall. Anyone dealt with this particular part before? Thanks. Merv

Thu Mar 08, 2012 8:52 am

I may have the same problem, I think, either that or they think they're not working because when I take my foot off the gas the van slows down a LOT

Thu Mar 08, 2012 8:57 am

Replace the brake light switches on the master cylinder.

99% sure this will fix your issues.

Thu Mar 08, 2012 9:00 am

themervino wrote: ...I feel it in the trigger on the pedal but can't seem to figure out how it works...

If it is the same as my 84 then there are pressure switches (2) on the master cylinder (no Trigger, no Roy).

Failure mode can be total or just gradual requiring you to really romp on the binders to set them off.

Not a problem (I think) until both have failed but then you need to replace 2. Can be done with everything else (except removable dash pod cover) in place. Flashlight, peeking thru windscreen, etc. If you're fairily quick you do not even need to bleed the system afterwards... just a drop or two may leak so have a towel on the floorboard.

Thu Mar 08, 2012 5:06 pm

Altoona wrote: Replace the brake light switches on the master cylinder.

99% sure this will fix your issues.

X2 - pressure switch go bye bye.

Wed May 09, 2012 8:03 am

I have the opposite problem.

Walking the dog last night, I noticed my brake lights were on. Van is parked, key out, and brake lights on! So the dog and I unlock the doors, and I tap the brake pedal a few times and they go off, but a few seconds later come back on. So this time I stomp on the pedal, and they go out again, and seem to stay off. A couple hours later I decided to check on the Van again, and yup, on again. This is last night around midnight, so I pull the number 8 fuse, which in my 84 Westy is the stop lights, cig lighter, and interior lights. With the fuse out, the brake lights stay off for good.

So that's the story.

Question 1: I've never tried stepping on the brake pedal with the Van off. Is it normal for the brake lights to work with the key out?

Question 2: What's wrong? Brake pressure switch? switches?

Many thanks!

Wed May 09, 2012 10:08 am

I've answered # 1 after some Samba reading. Brake lights are hot with engine off, keys out. So that seems to be working fine.

As for #2, I'm pretty sure it's one of the switches. Since both switches are wired together, you only need one switch for the system to work correctly. The second is there for safety. After trying the system with only one plug connected to different switches, I think I've found the problem switch.

I'm going to replace both since they only cost $3.75. I'll report back after I have them in.

Wed May 09, 2012 10:21 am

Re: Question #1
During my recent center brake light install, it seemed like the
brake light stays "hot" for only a minute or so after key off.

I'd prop the pedal with a stick, then momentarily turn the key to
run and then off again in order to stop the infernal chime.

A minute later the lights went off, although the stick was still in the
same place. Repeat the key on sequence & they'd come back...

Yes?

Wed May 09, 2012 10:55 am

My brake lights stay hot all the time. At least anytime I step on the pedal the lights come on.

It's the switch nearest the driver for sure. It's works intermittently. With both switches connected everything seems to be working fine. But if I let the Van sit for about 30 or 40 minutes the brakes will come on and stay on. Then if I unplug the problem switch they go out, but still function properly with only one switch connected (the switch near the radiator). With only this switch connected the problem seems to be gone, at least after 30 or 40 minutes they never come back on as long as the switch near the driver remains unplugged.

The problem switch must be tripping or something when the brake hydraulic pressure builds up over time or something? Not really sure. Seems like most people have the opposite problem with the switches. As they get older they clog and don't come on . . . strange mine won't go off? Or suddenly will "open or close" and come on?

Hope the new switch does the trick.

Wed May 09, 2012 11:33 am

chojinchef wrote: Altoona wrote: Replace the brake light switches on the master cylinder.

99% sure this will fix your issues.

X2 - pressure switch go bye bye.

x3 - They're cheap, a total PITA to replace, but you wont loose too much fluid (so no need to bleed system) and it fixes the problem.

Wed May 09, 2012 11:47 am

if you can buy OEM or the best ones you can.
we've had the cheap ones fail in very short time.. like 2 months..
on disassembly the cause was that the inside contact/plunger pushes the spade contacts further out if the brakes are pressed harder than normal.
this then creates a scenario that the lights will only comeon for hard pressing of the pedal and not light action as in rolling slow traffic..

just a word of caution.. we only use dealer brake pressure switches in family/friend VWs.

Wed May 09, 2012 1:54 pm

danfromsyr wrote: if you can buy OEM or the best ones you can.
just a word of caution.. we only use dealer brake pressure switches in family/friend VWs.

So true of many so called cheap replacement parts.
I also ask for the manufacturer of the dealer order parts before buying them.
Some are superior to others.

Tue Jul 03, 2012 3:11 pm

Sigeats wrote: My brake lights stay hot all the time. At least anytime I step on the pedal the lights come on.

Hope the new switch does the trick.

Hey Sigeats, did the new switch work for you? I've got the same problem presently.

Mon Aug 13, 2012 10:28 am

since I replaced my master cylinder I've had this problem. I might have had it before, but I noticed it after replacing they master and almost all of the brake components.

The new german master cylinder I got had the 3 prong switches and I needed to two prong so I reused my old ones. Thats when I first noticed it. The pedal has to be pressed a good amount down before the lights come on.

So I replaced the switches with new ones and the behaviour is exactly the same. I tried each individual switch one at a time (old and new) and they all behave the same.

What else can cause this? Air in the master? I bench bled it and the whole system a few times and am very happy with the brake response.

any ideas? Are there such things as more sensitive brake switches out there?

Mon Aug 13, 2012 10:46 am

For us non-mechanics it's not that hard to do this but it's a pain. I did it twice in a year. Longsuffering PO seems to have paid a mechanic to do it at least three times. It's a total crap design.

I've had it, I'm about to install a switch on the pedal like a normal car.

Mon Aug 13, 2012 10:49 am

Toxteth47 wrote: For us non-mechanics it's not that hard to do this but it's a pain. I did it twice in a year. Longsuffering PO seems to have paid a mechanic to do it at least three times. It's a total crap design.

I've had it, I'm about to install a switch on the pedal like a normal car.

do what? replace the switches? i'm not following...

Mon Aug 13, 2012 11:21 am

Yes, I mean "do" the replacement of the switches. By the time you go through this two or three times, I think it's worth it to get somebody to re-do the brake lights with a switch on the pedal. It's going to happen again and again. One traffic ticket and it's paid for itself. Again.

Mon Aug 13, 2012 12:50 pm

I've often thought of installing a momentary contact switch in/on/effected by the pedal action.
I don't see any need to remove or rewire from the master switches though.
just add a new switch that will connect the +12v around the OEM switches.

*note this may cause the dashbrake warning to light if you only bridge 1 3pole stock switch.

I haven't done this yet. but don't want to remove the OEM portion, just enhance it's speed/accuracy/reliability.

Mon Aug 13, 2012 1:24 pm

danfromsyr wrote: I've often thought of installing a momentary contact switch in/on/effected by the pedal action.
I don't see any need to remove or rewire from the master switches though.
just add a new switch that will connect the +12v around the OEM switches.

*note this may cause the dashbrake warning to light if you only bridge 1 3pole stock switch.

I haven't done this yet. but don't want to remove the OEM portion, just enhance it's speed/accuracy/reliability.

are you implying that the pressure switches are just inherently slow to activate?

I would think that you could just piggy back the connection to a contact switch off the existing brake light switch wiring. The second switch (at least on the two prong switch system) is just piggybacked off the first switch in the same circuit.

Mon Aug 13, 2012 2:39 pm

yeah I'd like my lights (on mom's van mostly) to lite when your foot first moves the pedal, not once hydraulic action reaches a certain point.
I've seen VWs where they almost never lite if light braking is used.

I don't tend to ride my foot on the pedal, and they say that the 0.5sec is XXX feet in reaction times. so sooner the better.