Dumb brake light question

[targatuesday]

Someone please educate me on the proper way to adjust the brake light switch on the pedal assembly of my 1971 911T Targa so the brake lights come on sooner. Right now I have to be pretty hard on the brakes before the brake lights come on. No brake lights under gentle braking.

[Richy]

You need to adjust the disc at the pedal assembly that activates the switch .

[edmayo]

Or you could remove the switch and adjust it. There is a locknut (7 mm wrench) and slotted screw. Use a ohm meter and and you can adjust to close circuit sooner or later.

[targatuesday]

Thank you Ed Mayo. I just found this same answer in an older thread and it is EXACTLY what I was looking for. Thanks for confirming.

[targatuesday]

Thanks to Ed Mayo as well as an old thread I found I was able to figure out the brake light switch adjustment that it seems many of us were not aware of. If you push your brake pedal and the brake lights do not come on as soon as you think they should I highly recommend adjusting the brake light switch. Takes about 20-30 mins start to finish.

First remove the pedal board to expose the pedal assembly underneath.

The Brake light switch is secured to the pedal assembly with 2 screws. Remove these two screws and then you can either make the adjustment without removing the electrical wires OR if your switch is crusty and corroded you may want to remove the wires and take the switch to your workbench.


Here you can see the adjustment screw and nut with the switch installed. The adjustment screw would be very difficult to adjust with the switch mounted.


If you remove the switch from the car you may want to inspect the contacts for pitting, carbon build-up, or other damage. Remove the adjustment screw and use a file to dress the screw surface as needed. You can also slide a file in from the side of the switch to clean up the inner contact. If your switch is beyond repair replacements are available from our host as well as other Porsche parts sellers.


HOW TO MAKE THE ADJUSTMENT:
The lever arm on the side of the switch is held in the OFF position when the brake pedal is not being used. As the brake pedal is depressed the lever arm moves in the direction of brake pedal travel until the lever arm makes internal contact with the adjustment screw. This contact turns the brake lights ON.

Turning the screw adjusts the distance the switch lever travels before making contact.

• Turning the screw CLOCKWISE adjust the switch lever so LESS BRAKE TRAVEL is required before the brake lights illuminate.
• Turning the screw COUNTER-CLOCKWISE adjust the switch lever so MORE BRAKE TRAVEL is required before the brake lights illuminate.

Is there a recommended adjustment? My old Clymer manual from 1972 states when the brake pedal arm moves 4mm from the rubber stop on at the base of the pedal assembly the brake lights should illuminate. One method to achieve this would be to wedge something 4mm thick between the pedal arm and the rubber stop, make the adjustment at the brake switch, then remove the 4mm thick wedge and test the brake lights.



TESTING:

• Adjust the screw but do NOT tighten the nut.
• Install switch in car and push brake pedal to ensure brake lights illuminate when desired
• Fine tune adjustment screw as needed until brakes illuminate at desired travel of brake pedal. (Make adjustments with switch mounted or not depending on what is easier for you but always mount switch and test after each adjustment)
• When screw is correctly adjusted tighten the 7MM nut.
• Make sure the 2 screws holding the switch in place are properly tightened so switch can not wiggle, slide, or move.
• Make a final rest to ensure brake lights illuminate when desired

Reinstall pedal board, carpet, floor mats and enjoy driving your 911 knowing your brake lights are illuminating when you push the brake pedal.

[Jim Morris]

Nice work. Thank you from those of us who are not experts.

[dogLeg]

Excellent instructions thanks!

[Fixer]

That is a dumb question.

Not expecting that?! Lol

Sorry, there are no dumb questions.