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Brake lights wont turn off?


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1976 D. 620. runs fine never really had a problem until today.

So if the truck isnt on and the key is out(in the off positon) the brake lights are still on,

If i pull the fuse it stops. i got down and checked the button (switch) thats connected to the brake pedal, and its NOT stuck. a little dirty but not stuck.

I also dont know shit about wiring unless its speakers. and now its to dark to really search through wires, so while I wait for the sun anyone got an idea?

much thanks

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just to be clear here....that is a normally closed switch......which means that if the plunger is NOT pushed, it will pass current. The plunger has to be pushed in to break the circuit. If the lights went out when the switch was disconnected, then it pretty much has to be the switch.....or as stated early, it's not be pushed in when the brake pedal is in it's "at rest" position. Maybe we're missing something in the description?

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make this EZer will reaaly harder to soem people.

which was EZ to begin with.


take both switches. Ohm them out

with switch plunger out the switch should be SHORT. Light come on.

With switch plunger IN should be OPEN



On the pedal there is a plate that the switch pluger supposed to hit(at least my 521 had one). The plat fell off thus the plunger would never get engaged. I JB welded a PENNY on there and all is good


you could have got a switch that was reversed but Im only guessing

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