Brake light not working until pedal is to the floor

[ohbugger]

Hello everyone,

I recently obtained my first Porsche after years of looking and patiently waiting... well you know the story. It's a 75 911 S with the 2.7 (I know of the issues, but I got what I think to be a great deal on it).

Anyway, I have many questions but have been searching the forums and learning quite a bit. The main issue I would like to fix now is the brake lights not working until I press the brake pedal all the way to the floor. I've read of the switch wearing over time, but how do I know which part to order for my year? The two that attach to the master cylinder, or the one by the pedal?

Thanks in advance!

[john walker's workshop]

it's a micro-switch with an arm that lays on the pedal. remove the wood floor board to get to it. you can bend the arm as needed. the switch on the master cylinder is for the dash warning light.

[ohbugger]

Great! I'll take a look under the floor board and post back if I encounter anything unexpected. Thanks John.

[porschenut]

I'd love to see a picture of how that switch is mounted to the cluster, if you have the time. I want to modify my '86 to use the mechanical switch instead of the pressure switches on the MC.

[ohbugger]

Forgot my camera when I went to the shop to tinker around, so I couldn't take a picture. But I found this image that shows the cluster - you can see the brake pedal arm sticking up and out of the picture on the left. The switch is held onto the back of the bracket in the center by the two screws you see. The gray arm sticking out from behind the bracket is what touches the washer behind the brake pedal.



I rolled the nut behind the washer back, so now the pedal has more free play but it trips the switch when the brakes are actually applied. Haven't driven it to test yet; hopefully will this weekend.