Check the tail light ground wires.
head lights won't work, no power to them, signal works , reverse lights work
cause the head lights r one the head of the car, the front and the taillights are on the back of the car also known as the tails
Head lights
Yes, the ignition on a trailblazer can cause head lights to work improperly.
loose head light switch
a Phillips head screw driver
A back tooth can cause swelling at the back of the head. This is especially true if your back tooth is infected.
Low beam head lights? High beam head lights? Day time driving lights? Tail lights? Brake lights? Dash lights? Signal lights? Dome light? Glove compartment light? Trunk light? License plate light? Courtesy lights? Give us a clue.
Do you mean the turn signal lights/blinkers? Check the turn signal flasher mounted on the fuse box in the lower left-hand side of the dash below the steering wheel. While you're at it, check the fuse for the turn signals and replace if necessary (use the fuse guide on the back of the fuse box cover to locate the turn signal fuse). If neither of those work, check the wiring or have someone else do it for you.
It is the turn signal switch combined with the head lights, wipers, etc.
That sounds like a grounding problem, probably near the right side lights. It might be a rusty or disconnected ground wire.
The dash lights and lights to the gear shift panel are grounded through the radio, be sure that the radio plug and ground to radio are connected. If you have taken out the radio you may try grounding the plug wire that connects to the radio lights.