03 Trailblazer - No Brake Lights

[phbalance0904]

2003 Chevy Trailblazer LT

Ok, so when changing a blown reverse light I discovered a lot of corrosion on both the tail light circuit board and the wiring harness. Ignored and just switched the bulb, but since they come 2 to a pack, went ahead and switched the other side too. Hooked back up and no tail lights; at all.

Fast forward:
Replaced all bulbs, both circuit boards, both wiring harnesses and confirmed all fuses (front box and the box under the back seat) are all good, then replaced them just to be sure.

Results:
Now the hazards work, the reverse lights work, the turn signals work and the center brake light on the gate works. Brake lights in the tail light assembly don't work. Note: when cycling through/testing the various lights (hazards, reverse, turn signals, etc) all 3 lights in both tail light assemblies will work in one fashion or another, but the when pressing the brake pedal, no brake lights in the tail light assemblies.

My first thought is that it's something in the wiring itself. That said, does anyone have any other thoughts? If this seems accurate, is there a wiring schematic or something of the like that I can review to try and trace the wiring issue?

Thanks for any help you can provide

 

[MAY03LT]

...the center brake light on the gate works. Brake lights in the tail light assembly don't work.

Check fuse #34 in the rear fuse box. This fuse will only have 12v on it when the brake pedal is pushed. If you have 12v there, then check for 12v at the light blue wire at each tail light connector.

 

[TGFB87]

In addition to the checks mentioned above, I know that the taillight circuit boards were once covered under a recall for failing. If you have not had that recall done, or if you are unsure, you may want to check with a dealer to see if you are covered by such.

I know I had mine replaced twice because of the recall...

 

[Mooseman]

And if you download my manuals, they have the wiring schematics which would help in tracing the wiring. Link is just below.