74propu
Full Access Member
- Joined
- Aug 8, 2015
- Posts
- 687
- Reaction score
- 242
- Location
- florida
- First Name
- austin
- Truck Year
- 1974 1980 1986
- Truck Model
- c10s/b c10 s/b c10l/b
- Engine Size
- 5.3 / ?/454 tbi
Orange wire is + 12 volt to brake light switch . White is hot after brake light switch to turn signal switch where the brake lights are canceled for the left side when the left hand turn signal is activated and the same for the right side . so if all the 4 ways and turn signals work but no brake light on one side then the turn signal switch is bad. you can test this by getting a new one and just plug it in and see if the brake lights work before you take the steering column apart/