brake lights don't work :(

[K85 Octane]

Here's my scenario. Wired my truck months ago with EZ Wiring kit, everything has worked up until a week ago. '85 blazer

What works:

blinkers
running lights
flashers
reverse lights
trailer brake controller notices brake pedal movement, so it's getting power to brake switch and leaving brake switch correctly.
Flasher fuse and brake fuse are good, even tested with meter

I know at some point the brake light wire runs into the blinker wires, considering they are the same filament and I don't have a "brake light" wire going to the back. I can contort myself pretty good, looking up under the dash and checking things, but getting out is sometimes tricky, so it's life or death struggle each time I attack this

Any pointers before I continue? Haven't had a chance to multimeter test my wires going down the frame.

 

[Fordum]

OK, I can help some. Turn on your headlights when its dark out, and see if the turn signal indicators in the dash light up slightly.
If so, its a bad ground.

Otherwise, the bulbs are good, the wiring going to the rear is good, because the bulbs light when you turn on the signals.

The most common problem, is the emergency flasher switch.

If you can see the brake lights against a wall or something, hold down the brakes and wiggle the heck out of the emergency switch.
Turn it off an on a few times.
Lots of times that will cure it.

Otherwise, it may be in the turn signal switch, but usually only one light will not work if its that.

Oops, the flasher is the second most common. The first is the tow brake controller if you have one.

 

[K85 Octane]

I guess I forgot to say:

emergency lights work
brake lights stopped working before brake controller was installed. BUT brake controller still works

I'm taking this thing out Sunday with or without brake lights, it's my first Sunday off and I gotta get it out in the dirt again. Would rather have them working but I'm completely stumped as to what could be wrong? Where does the "switched hot" wire from the brake pedal switch normally go and how does it splice into the right/left turn signal wires that chase down the frame rail?

 

[Fordum]

The brake light switch goes directly to the turn signal switch. That switch splits it to the left and right lights.
So, if your rear turn signals work, then everything from the turn signal switch back is good.
It has to be the white wire from the brake light switch to the turn signal or the turn signal switch its self.

This is also the wire the brake controller uses.

 

[K85 Octane]

ooooo now THAT is super helpful

the white wire IS being used my the brake controller
the turn signal cam in the column is brand new with about 700 miles on it

so I guess chasing the white rabbit is what I'm after
very interesting

thanks J

 

[K85 Octane]

Thanks J

The multipin plug that comes from the turn signal cam was a tad lose on the side with the white wire. The rest of the plug was tight. I pushed both sides back together real tight and I now have brake lights. If this happens again, I might throw a ziptie around them or some tap. Both connectors are brand new darn it.