early 911 swb brake light switch

[lars1965]

I had issues with my rear brakelight and have fitted a new pressure switch to the mastercylinder on my 1967

New brake light switch fitted…. the old one was almost stuck , rusted tight .

status:

when i hit the brake pedal engine running with light OFF , right brake liight wery sharp, left only half the light but visible

HEADLIGHT ON: left brakelight stay ON , WITHOUT pedal pressed,? I press the brake , then the right light up the same level as the left…..

I have tried to reverse the wire on the brake switch , the problems also reverse?

I have tried several bulbs same watt , but different brand, the car is very sensible for what kind of bulbs I put in, ( but this is the best i can get)

the 2 filament bulb can only go one way in, and it have the 2 wires to the left bulb holder as in the diagram
all bulb holders etc, grund CLEANED good.

can the pressure switch be adjusted in/out for better function

any ideas?

rg.Lars

[edmayo]

Pressure switch non-adjustable and wire orientation doesn't matter.

[lars1965]

thanks Ed , and what do you suggest then?

[NeunElf]

Lars,

It sure sounds like the high-wattage filament in your left running/stop light gets power when your headlights/running lights are on and the low-wattage filament gets power when your brake switch closes. That's the opposite of what it should be.

If everything's ok on the right side I can give only two explanations:

1. The wires are reversed at the running/stop light bulb holder on your cars left side, or
2. You have the wrong light bulb. Maybe there are bulbs that work the opposite of what your Porsche's designed for.

Try swapping the light bulbs right and left. If you now have a dim stop light on the right and a bright running light on the right you can buy a correct bulb.

If the problem stays on the left side, just reverse the wires on that bulb holder. Even if it matches the wiring diagram now, it should work correctly if you reverse the wires.

-----------------------

By the way, I just went out to check the wires on my 911 and it's 100% dead: ZERO volts across the battery! Sorry, but I have to blame you.