brake light on dash?

[kilog55]

is this light for the e-brake or is it a warning light that something is wrong in the brake system itself? cause mine is on but PO put tape over it cause lens is broken

[ezernut9mm]

warning light. there is a tutorial for recentering the proportioning valve in the tech section i believe. fordman has new/used light assy's for sale too.

[FORDification]

Do a search for "brake warning light" and you'll get plenty of info on the subject.

[kilog55]

nevermind

[Supermike]

The better question is, how do you know if it's working if it's only supposed to light up when there's a problem? There was some debate that it's supposed to turn on briefly when the truck is started, but that was never confirmed and I don't believe that's the case -- at least not for the 67s.

??

[Thunderfoot]

Couple ways to check it...
First is to watch the light when you are "Starting" the engine. This is when the key is in the "Start" Position it should come only then.

The other way is to unplug the connector from the "Brake Warning Switch" on the brake line and try grounding each wire. One wire is the ground to for the light and the other is a wire that goes to the ignition switch and the ignition switch will ground it when the key is in the "start" Position for the light to come on. The brake warning switch is grounded and when the valve in there moves from different pressure caused from a leak or what ever, it switches over and grounds making the ground path for the brake warning light.

Here is the wire diagram of this... http://www.fordification.com/images/sch ... glight.jpg

[Supermike]

Ugh. I guess I'll start by replacing the bulb... but I'm afraid if I do, it'll come on and be stuck "on". After all, why would it burn out?

In all the searching I did here, it was never settled that it DID in fact come on for everyone when starting.

[fordman]

mine does come on when you turn the key to on.

[kilog55]

well that makes 2 so far

[Supermike]

What I'm not clear on is whether this would be the expected/standard behavior for EVERY year of our trucks, or perhaps just later years? I thought the Ford documentation said the only time it came on was when there was a problem.

I wonder what Keith knows?

[Thunderfoot]

1967 (the odd child) is a little different (I keep finding more wiring differences all the time ) in that it only has a single wire to the brake light switch, but it still goes through the ignition switch so that it can be grounded during starting to show you that the light is working.
You can unhook this wire and ground it and the light should come on (with the key on).
There is always the possibility that the ignition switch contacts for this ground connection could go bad and not allow this "light check" function to work or a bad ground connection to the ignition switch, etc...

If you look at this diagram http://www.fordification.com/images/sch ... ghts02.jpg at wire 511 you will see where it goes to the ignition switch and then 511A is also connected to it there. 511A goes to the Brake light, this 511-511A is the ground connection for the bulb and 460 is the power for the bulb.

So, yes all years of our trucks the light should come on when you start the truck if all the connections, ignition switch, and wires are working correctly.

[Supermike]

Well, crap. As expected, the bulb was burned out. Popped in a new one, and the dang thing lights up like a Christmas tree. Only problem is, it stays on.

So thanks guys for helping me figure out my brakes aren't working right, but... dangit! Now I've got to figure out how to fix something else.