I have a 1972 F100 Sport Custom. I got it a few months ago. There is the red light next to the switch for my headlights. I don't know what it is there for. It lights up when the key is turned and it stays on. And it gets really hot. I touched it the other day after driving for about 1 hour and a half and it burned my finger. Does anyone know what it could be there for?

 

It is a Brake Warning lamp. That is telling you there is prolly a pressure difference between the front brakes and the rear brakes. And there isn't supposed to be. Did you have any brake word done lately? If not you better check out your complete brake system.

 

Awesome, thank you. I'll have to check it out.

 

Evidently, someone changed out the red lens on the brake warning light to a non-descript lens.

It should say this when it's lit up.

 

The chrome bezel looks more flat than a Ford one also. Must be an aftermarket replacement.

 

Lotta talk about this same thing all of a sudden... coincidence???

 

Many people may not know what this light means, how it works or what it's telling them. There are only two things that would cause this warning light to come on and stay on; The brake system was bled out and a pressure differential was created during the process and tripped the warning light or, there's a legitimate problem in the brake system that's losing pressure/fluid that caused the light to trip.

....ok, maybe a 3rd possibility --there could be a short in the wiring to the brake warning light but, not highly likely. More probable that it's the other two possibilities causing it to stay on.

 

"Their light bulbs just came on".
(Sorry, I couldn't resist)

 

The Brake Pressure Differential Valve Warning Lamp Switches have been troublesome turds since day one.

C7AZ-2B264-A = All 1967 FoMoCo vehicles / C8AZ-2B264-A = 1968/69 Passenger Cars & 1968/79 F100/350, Bronco & Econoline.

 

[QUOTE=NumberDummy;16715236]The Brake Pressure Differential Valve Warning Lamp Switches have been troublesome turds since day one.

How so?

 

Really? I'm surprised to see you say that. I have had a lot of people want to buy them over the years. But for the wrong reason. The 1st thing I would ask them is if they were changing it because of brake fluid coming up the middle of it and leaking out? 9 times out of 10 they would say YES. Then I would tell them the bad news that they actually needed the differential/proportioning valve. There isn't supposed to be any brake fluid under it. And that nylon switch SURE wouldn't hold the full high brake pressure! Only metal flare fittings can. For those other readers out there, the "seals" on either side of the "valve piston" in the pic below is what was seeping. And the brake pressure was sending that seeped brake fluid up the center of the switch.

 

From the late 1960's thru the 1980's, I passed out 100's of these puppies to mechanics, most were C8AZ-A's.

And btw, I never asked anyone why they were replacing it, because I loved that fat commission check I got every month.

1975: When I went from Walker-Buerge to Crenshaw, I was offered a $1000.00 raise (from $1300 to $2300). When I told the p/m at W-B what I was offered, he said you'll never make that much.

I actually made more than that and I made copies of the salary & commission check stubs, sent them to him for several months!

 

Ok, back to the original question, what makes the switch a "turd"?

 

There had to be reasons why so many were passed out to mechanics.

If I thought about it, I might remember that at the same time, I only passed out one specific mechanical part to one mechanic.

 

Fail........