No brake lights but turn signals but hazards and override Trailer brake lights work

[JeffKPDX]

So I'm chasing down a gremlin in a 92 F250 7.3 idi on the day I'm supposed to be leaving for a 10 day trip. Any advice appreciated. Here's the situation.

I got no brake lights but my turn signals work and the hazards work also. Additionally, if I apply the manual override brake for the brake controller when that is connected then the lights come on. I've replaced the multi-switch and checked all fuses. I ruled out that it is a ground since the turn signals and brake lights will still come on. I think it might be the brake light switch but I have already replaced that once so I was skeptical it was that at first. I'm off to but another and swap out but I'm not hopeful that will solve anything.

I recently installed the trailer brake controller. It worked at install but now that the lights are out it only operates if I push the manual override button to apply brakes. I'm not familiar with how that wiring ties in but I could see that being a fail point as well since it seems that it is getting it's brake pressure reading from the switch as well? It's a little over my head though so any insight is welcome.

Thanks!

 

[Double-S-Diesel]

Ive had the multi function switch do that before.
check wire where the brake controller wire attached to the switch wire to make sure it is not broken.
other than that make sure the switch is being depressed when you push the brake pedal, I have had trouble here also with the oreintation of the switch .

 

[ttman4]

What kind of trailer brake controller you install?

I got same problem. Also I fall into a rt hand curve & my dash Anti-Lock Brake lite comes on till I straighten up.
This last Tekonsha controller, I think Prodigy, that I installed on my '90CCDually instructions said to "Be sure to hook the (don't remember now which one) wire to the ??? colored wire coming up the steering column.
I did & I kind'a think all this is part of my problem. Need to get it fixed tho.

 

[Big Bart]

Sounds like the brake light switch is not getting power, is bad, or not adjusted.

As I recall the brake controller taps into the brake light wiring. So when you manually use it it powers the brake lights. Sounds like the truck is not supplying power to the brake switch perhaps.

Thoughts

1) Check the fuse for the brake lights.
2) Test for power at the brake switch and that the switch is working.
3) Make sure your brake controller is hooked up right.
4) If you have any odd trailer wiring tap system, that you hooked it up correctly.

Let us know what you find.

 

[franklin2]

When you are messing the with the brake light switch, carefully check the wires to the switch. They like to break. Ford uses a hokey setup, where they use the "play" in the brake pedal pin to actuate the brake pedal switch, there is no adjustment. But the whole business floats back and forth on the pedal assembly arm, so the wires are moving back and forth each time the brake is applied. Ford has used this same setup for many years.

 

[ttman4]

Sounds like the brake light switch is not getting power, is bad, or not adjusted.

When you are messing the with the brake light switch, carefully check the wires to the switch. They like to break.

Well I got brake lites now.
Both wires to/from brake lite switch were broke off. Fixed & all is good.
Amazing what I find and fix when I take time to look.