Topic: brake light pressure switch

[truetriplex]

My Thunderbird has developed a problem with the brake light pressure switch, and I am hoping that someone has seen this before and knows the cure. This is a recent front brake conversion from drum to disc. The switch is threaded into the distribution. and then the two leads are plugged in to the bullet prongs on the switch.  I can hit the brakes 2 or 3 times and the lights come on and work perfectly. Then they stop working and the switch is bad. I replace it and the same thing happens.  I know that the switches are made overseas, which may account for the problem.  Is there a simple cure, other that converting the brake switch to the pedal, that you can suggest, or a better part manufacturer to use?

[Bob Gaines]

My Thunderbird has developed a problem with the brake light pressure switch, and I am hoping that someone has seen this before and knows the cure. This is a recent front brake conversion from drum to disc. The switch is threaded into the distribution. and then the two leads are plugged in to the bullet prongs on the switch.  I can hit the brakes 2 or 3 times and the lights come on and work perfectly. Then they stop working and the switch is bad. I replace it and the same thing happens.  I know that the switches are made overseas, which may account for the problem.  Is there a simple cure, other that converting the brake switch to the pedal, that you can suggest, or a better part manufacturer to use?

The vintage Mustangs use a brake light switch at the pedal. The direction of this forum is factory correct parts and problems associated to that end. As much as we would like to help a fellow Ford enthusiast you may not get the answers you seek here . Hopefully someone here may have some insight on a similar conversion and T bird related proportioning valve with brake light switch.You may search some more for a T bird related forum. Best of luck solving your problem.

[Bossbill]

Usually when a simple switch goes bad like yours it would indicate either an intermittent direct short to ground or a very high amperage problem. We can't rule out bad switches, but testing should get you to a solution.

I usually use a test rig I made that uses a 10 amp circuit breaker (like your power window circuit might use) with alligator clips on the end. Simply install the test leads between the battery and the brake light side of the circuit and see if the circuit breaker kicks on/off.

You could also use a DVOM (wired as above) with amperage measuring capability, but these have a fuse inside so be ready to replace it. This would tell you how high the amperage is within limits of the DVOM readout. If you use a circuit breaker rating less than that of the DVOM you can save the DVOM fuse if a short occurs.

If the breaker cycles or the DVOM fuse blows the you need to investigate further.
I would try the shake test and wiggle the harness around while the lights are on. You might have to visually inspect the wiring front to rear.
There are also short identifier kits available, although I haven't tried them.

[jwc66k]

My Thunderbird has developed a problem with the brake light pressure switch, and I am hoping that someone has seen this before and knows the cure. This is a recent front brake conversion from drum to disc. The switch is threaded into the distribution. and then the two leads are plugged in to the bullet prongs on the switch.  I can hit the brakes 2 or 3 times and the lights come on and work perfectly. Then they stop working and the switch is bad. I replace it and the same thing happens.  I know that the switches are made overseas, which may account for the problem.  Is there a simple cure, other that converting the brake switch to the pedal, that you can suggest, or a better part manufacturer to use?

What year T-Bird? Your use of the word "distribution" sounds like the wiring you are concerned about is for the brake warning system.
Jim

[67gta289]

+1 we would like to help, but being a T-Bird is a bit off the typical mark here, and making that a modified T-Bird makes it even more so.

What year car are we talking about?  Can you include a picture of said switch so that we can eliminate conjecture?

[67gta289]

I'm thinking that the OP is asking about 2B264, referring to the attached document.  If so, the C7AZ-2B264-A can be found used and in working condition.  That is what I prefer to use over aftermarket stuff.

[Bossbill]

I'm thinking 13480.
The OP was talking about converting to a brake pedal switch.

[67gta289]

You might be right.  The only thing that threw me was that the switch was "threaded into the distribution".  It could be a 64 version with the 13480 wired to the master cylinder. 

I'll go back to my previous request for a picture, until we get more info we are stuck.

[Bossbill]

Yes, we are guessing. I'll also guess that since dual bowl masters have no provision for the switch he is using a port off the distribution block for the switch.

California Specials and 67/68 Shelbys can also have similar issues with their 6 pack of taillights.