86 Brake Lights come on late..adjustment anywhere?

[Storage Man]

Have to almost stomp on the brake pedal to get the lights on.
Was thinking the sensor should be on the pedal shaft but can't find it in the Bently manual.

[cabmandone]

Aren't they located at the brake master cylinder in the trunk? IIRC that's where the sending unit is in my 85.

[tailwind22]

There are two pressure activated switches located on the master cylinder. I had no brake lights on my 88 and just replaced both. It solved the problem but they are tough to get to and it was a time consuming process. I have to believe yours are in the process of going bad, thus behaving like they are.

[kjchristopher]

Mine did that when the sensors were failing. Bought two from out host and replaced in about twenty minutes. Super easy with the correct offset wrench, which I happened to have in an toolbox full of my late grandfather's tools.

Do a search on replacing the brakelight switch and you'll see plenty of info.

[p911dad]

+1 And, I didn't need to bleed the system, just topped up the lost fluid. Make sure to place rags under the master cylinder to soak up the small amount of brake fluid that will leak out. I put a bit of Teflon tape on the brake switch threads to make it leak proof.

[Storage Man]

Offset wrench?
Anyone have a part number?
What I see is $129.00ea......

[DRACO A5OG]

You really do not need any special tools just remove some of the fresh air components from the trunk area to gain easier access to the rear switch, for installation the rear one, it just needs to be snug then 1/4 turn for torque, the new switches come with a crush washer.

Here, I must recommend OEM from Porsche, aftermarket ones just do not hold up as well. Sorry Wayne. I think you can request OEM from our host too, just call them.

For me, anytime I open the brake lines for whatever reason, I like to press the brake pedal in about 2 inches just to be on the cautious side, you can use a 2X4 and slide the seat up, then crack open the switches, the front one I used a deep socket the rear just a box wrench. It is pretty straight forward but access to the rear is very tight.

Another OCD thing is, I like to drip some brake fluid on the new switches inlet, just to make sure an absolute less chance of any air in the system.

Hope that helps.

Jim

[JFairman]

I changed both of them too when someone pulled up next to me and told me I don't have brake lights. When I checked them that night sure enough light around town brake pedal pressure didn't turn them on and only harder pedal pressure turned them on.
I got them from a Porsche dealer and they cost a little less than they do here. Also, the ones from here are silver cadmium or zinc plated and the ones from the dealer are gold cad plated like most other porsche parts and look higher quality.
I wet them with brake fluid before installing them and bled the brakes afterward to get any tiny air bubbles out of the master cylinder.. and last I checked the brake lights work with light pedal pressure now.

[wayner]

Is there a microswitch for the pedal that we can use, perhaps form a later car?

I've wondered if light break pressure in traffic actually has enough pressure to activate the ones on the master cylinder or not?

[Storage Man]

Originally Posted by DRACO A5OG

You really do not need any special tools just remove some of the fresh air components from the trunk area to gain easier access to the rear switch, for installation the rear one, it just needs to be snug then 1/4 turn for torque, the new switches come with a crush washer.

Here, I must recommend OEM from Porsche, aftermarket ones just do not hold up as well. Sorry Wayne. I think you can request OEM from our host too, just call them.

For me, anytime I open the brake lines for whatever reason, I like to press the brake pedal in about 2 inches just to be on the cautious side, you can use a 2X4 and slide the seat up, then crack open the switches, the front one I used a deep socket the rear just a box wrench. It is pretty straight forward but access to the rear is very tight.

Another OCD thing is, I like to drip some brake fluid on the new switches inlet, just to make sure an absolute less chance of any air in the system.

Hope that helps.

Jim

Hey Jim, thanks.
Happen to have he part number I am looking for?
Are the $129.00ea?

[Storage Man]

Originally Posted by JFairman

I changed both of them too when someone pulled up next to me and told me I don't have brake lights. When I checked them that night sure enough light around town brake pedal pressure didn't turn them on and only harder pedal pressure turned them on.
I got them from a Porsche dealer and they cost a little less than they do here. Also, the ones from here are silver cadmium or zinc plated and the ones from the dealer are gold cad plated like most other porsche parts and look higher quality.
I wet them with brake fluid before installing them and bled the brakes afterward to get any tiny air bubbles out of the master cylinder.. and last I checked the brake lights work with light pedal pressure now.

This is what I'm trying to avoid. Mild braking is nada, firm braking they come on. Might be on the cusp of needing them replaced but not into spending $260 for a set right now.

[timmy2]

113945515H is the switch number.
Pelican has them from Porsche for $20 each. ATE are $15 each.
Pelican Parts - European Automotive Parts and Accessories - Porsche • BMW • Mercedes • Volkswagen • Audi • Saab • Volvo • MINI

[Storage Man]

Thanks timmy2. Well that's a lot better....
I'm assuming I need two of these and some brake fluid.
Any break fluid from our sponsor?

[timmy2]

The part number also cross references to VW.
For brake fluid I use the ATE (if it is still available).

[Arne2]

Originally Posted by wayner

Is there a microswitch for the pedal that we can use, perhaps form a later car?

Plenty of threads on adding a mechanical switch. Lots of us have done it. Here's one:

Safer stop lights

[Storage Man]

I read someone used Teflon tape to resell these on instal, or are the crush washers for that?

[kjchristopher]

Originally Posted by Storage Man

Offset wrench?
Anyone have a part number?
What I see is $129.00ea......

Something like this:


Should be able to find it in the correct size for cheap.

[DRACO A5OG]

No Teflon needed, just make sure 1/4 turn past snug. oh yeah, go in straight. :-)

Don't worry it is not that complicated, just tight a space for the back ones. ATE Gold, would be best for our cars. Blue stains but the same. I doubt you will need any but better safe then sorry. Plus you may want to do a quick flush anyways. While you are in there. Remember if you do the helper method on the pedal, DO NOT GO ALL THE WAY DOWN TO THE FLOOR BOARD, use a block of wood to prevent dropping the pedal to the floor, it could damage the MC.

[Storage Man]

Originally Posted by DRACO A5OG

No Teflon needed, just make sure 1/4 turn past snug. oh yeah, go in straight. :-)

Don't worry it is not that complicated, just tight a space for the back ones. ATE Gold, would be best for our cars. Blue stains but the same. I doubt you will need any but better safe then sorry. Plus you may want to do a quick flush anyways. While you are in there. Remember if you do the helper method on the pedal, DO NOT GO ALL THE WAY DOWN TO THE FLOOR BOARD, use a block of wood to prevent dropping the pedal to the floor, it could damage the MC.

Thanks Jim. I have a helper.
Dumb question but here goes: Pedal pushed down 2" before during or after removal of the old part.

[Storage Man]

Originally Posted by kjchristopher

Something like this:


Should be able to find it in the correct size for cheap.

Thanks chRis.
What size did you use to get these off.