Adjusting Brake Light Sensor/Switch?
 

Hi,

Is there a HOWTO procedure on how to adjust the brake light sensor/switch?

I find I have to apply a fair amount of force on the brake pedal in order for my brake lights to switch on. This can be rather stressful when driving in peak traffic in wet rainy conditions :eek:

There's no adjustment. The switches need to be replaced.

Oh OK. Is this an easy task? Is there a URL outlining the procedure?

They are the things on the master cylinder. Try ging them a clean (on the inside) with some brake fluid. If this doesn't help you may need to replace them. They may be the same part, or size, as a VW one without the Porsche prices.

I had to replace mine on an '87. It is easy.

You just need a deep socket (23mm I think). Have plenty of rags about underneth. Remove the wire plug and loosen with the socket. Once it is hand loose, stage the new nearby. If you are quick, you can switch them and not lose brake fluid or get air into the system forcing you to perform a bleed.

There are two sensors on the '87, They are $8-12 ea here on Pelican. I have heard that there is a volkswagon part that is the same only cheaper if you are willing be "unpure"...


On mine, it looked like this: http://www.pelicanparts.com/catalog/images/wayne_new/19mm_master_cylinder.JPG

This picture shows the rear installed, it is the silver part with the gold spade, the front is not installed. This is the assembly below the brake fluid assembly in the front boot.

HTH,
Paul


P.

Behtley's Manual:
http://forums.pelicanparts.com/uploa...1123469937.jpg

The switches are not 'unpure' ... just VW parts made by Hella & supplied by Ate, originally listed in the Porsche parts catalog with VW part numbers ... so your options are many for a source!

The pic posted above is of an un-boosted master cylinder, not a '77+ vacuum-boosted master cylinder! The diagram below has the correct master cylinder with the two VW switches off the side.

This topic has been discussed to death ... do a search!

http://www.pelicanparts.com/911/911_...978-83/6-4.JPG