[97/4.3Shane]

so I’ve got a 97 s10 4.3l single cab 2wd and the front turn signals and brake lights do not function,but headlights and marker lights do however,but I checked all fuses. Grounds up front and went ahead and replaced the directional flasher,all my wiring looks good up front no ground issues nothing is chaffed no bulbs are burnt,but In the rear the guy before me spliced in a trailer plug and their is a loom of wires coming from the main harness not connected to anything,he used the plug coming out of if and plugged in a 3 way and the other plug is connected to the housings on each side w one black wire hangin…it sucks because I don’t have a multimeter or test light I’m gonna try and get one this week,but I’ll post pics

 

[oldeerslayer]

The hanging black wire is likely the ground wire. If it's not hooked up I'm surprised any of the lights work. It bolts to the frame on the inside right below the left rear tail light with a screw that has a 13mm head.

 

[Rhotpursuit]

The trailer wiring is also suspect...they always seem to be.