[Duracrap]

When i hit my brake pedal my running lights come on 01 gmc 3500 duramax

 

[roachwe]

Sounds like a tail brake bill had shorted out between brake and park lights.

 

[Duracrap]

When i turn on my running lights all 3 brake lights come on. What is tail brake bill?

 

[roachwe]

Tail brake light

 

[Duracrap]

Thanks for your input i figured it out.

 

[roachwe]

What was the issue so others can learn?

 

[Duracrap]

I unhooked my trailer brake box wirirng harness from fuse block under dash and they work fine now. When i unplugged it the red wire came out of plug so it might of been put in wrong pin hole. So i still gotta figure out the brake box but my lights are functioning correctly