The Stovebolt Site Forums The Shop Area The Electrical Bay Brake lights wont turn off...

I attempted looking thru other threads and couldn't find anything on this. I got home from a ride yesterday and noticed my brake lights wouldn't turn off; as if i was pressing on the brakes. its happened a couple times where i would have to just press the brake and they would then turn off; not this time... Is this some relay? fuse? or a bad ground? maybe something down around the master cylinder? ANY input would be veryyyy helpful!! thanks guys.

Kevin

the brake lights are mechanically controlled by a small switch on the lower firewall next to the pedal shaft, likely that's the problem, might be the arm that activates it bent or broke, or the switch itself is defective

Bill

on the interior of the cab? or exterior...?

lower firewall = under the hood below the fold .... should be some pictures in the shop manual, if you don't have one look here

Bill

i couldn't quite find any specific picture that helped identify... I suppose i will just go poke around under the chasis near the master cylinder and see what i can see.

Don't know if your truck is totally stock or not. On mine, I have a plunger type switch mounted under the dash that simply presses on the top of the brake pedal arm. When pedal is pressed down, plunger extends out and switches on brake lights. Bracket can get bent easily which leaves lights on.

Bruce - your hot rod is nothing like stock, early trucks had pedals thru the floor, not hanging from above

Kevin - it's not around the MC, it's mounted on the bottom of the toe board right beside the brake pedal arm, small switch with 2 wires

Bill

its not fully stock... and when another well educated wrench head took a look at the truck a little back, he said it had been fitted with a much larger brake booster. I inspected all around and couldn't find any type of switch or electrical wire near the brake arm, linkage, etc... there is some solenoid/relay "thingy" between the arm of the brake and clutch on the firewall that has two wires going from it direct to the fuse panel? but there is no protruding arm or anything from it. ?

well then you've got a hot rod too, no one but you can tell what kind of "thingies" might have been pasted on it - need to specify this kind of info when asking about old trucks, if the brakes have been upgraded then you probably have a brake light switch in the fluid line from the MC so that hydraulic pressure activates it - problem could be anything, including a bad MC or other brake problem

Bill

The "thingie" you mention sounds like the right one. the arm isn't very long and could be overlooked from the wrong angle. Do you still have the stock brake and clutch pedals?

So the next step.... Trace all of the fluid lines to/from the MC looking for wires connected to some sort of switch? the "thingy" that i described isnt the switch you were talking about? Its not a "hot rod" but only a couple things were done, i.e. the brake booster.. Its braking perfectly fine. what other brake problem would trigger something like this?

what I've been talking about is the factory arrangement, which you don't have - if you don't have any idea what you do have, nobody here can tell unless you post some good pics of the setup - you might have better luck taking it to a mechanic, or the person who looked at it previously

Bill

[IMG]http://i222.photobucket.com/albums/dd2/uofomoose/Dorothy%20pics/th_d1.jpg[/IMG]

here's a picture of the "thingy" to the right of the brake arm on the firewall

Update: i added the photo to the photobucket link under my info

from your pic it looks like the stop switch Bill refered to is broke.
It should have an arm on it.

It should look like this

And I'm guessing that's my problem.... Suppose a $6 part isn't that bad. But not being able to drive till I get the part; rough!

Try a few of your local parts stores. They might have one on the shelf.

if you have a napa in your town its part number ech SL128