So, I have a 1976 914 and decided to replace the master cylinder with the beefier 19 mm one from 914rubber and also swap out the front brake lines to the calipers. Got that done, bled the lines, brakes are fine, no leaks. However I see that the brake lights are always on when the car is running/ignition switch on (just to clarify that they are not "always" on - of course they are off when the car is off).
In reading about this issue here on the forum it seems that I'm getting confused between the sensor/switch on the MC vs. the brake light switch at the pedal. I've read that the sensor/switch at the MC needs to be reset by pushing in the "plunger"...but the one on my MC doesn't have a reset button/plunger. I'll investigate the switch at the pedal but the brake lights worked fine before the MC swap so I'm doubtful that would be the cause. I've attached some pics of the sensor on my MC.
So, can someone clarify what exactly the switch/sensor on the MC does...vs what exactly the switch at the pedal does?
Would it be sensible to purchase a new sensor/switch for the MC - one that has the reset plunger?
What would be the most likely remedy given that the MC is new and at no time did I "mess" with the pedal travel (other than whatever was needed to insert the rod into the new MC)?
Thanks in advance.
Wally
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Full Version: Brake lights always on
That switch activates a light on the dash.
If your brake lights are always on, you probably have the brake light switch incorrectly positioned. Its easy to do wrong when installing a new MC.
You will have to pull the pedal board back out to reposition the switch.
If your brake lights are always on, you probably have the brake light switch incorrectly positioned. Its easy to do wrong when installing a new MC.
You will have to pull the pedal board back out to reposition the switch.
QUOTE(ChrisFoley @ Oct 7 2022, 01:28 PM) 
That switch activates a light on the dash.
If your brake lights are always on, you probably have the brake light switch incorrectly positioned. Its easy to do wrong when installing a new MC.
You will have to pull the pedal board back out to reposition the switch.
QUOTE(ndfrigi @ Oct 7 2022, 05:31 PM)
Many thanks for the prompt replies. Turned out it was the switch at the pedal. Apparently when installing the new MC I managed to nudge the lever on the switch to the side of the large "washer" on the pedal that activates the switch/brake lights. All good now - was able to the car on a rally yesterday as planned - sweet!
You guys are the best...!
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