2003 Gmc Sierra Tail Lights Not Working

Electrical is not my strong point so any help would be.

2003 gmc sierra tail lights not working.

When i checked the wires at the tail light only the wire that worked the turn signals had juice the other 3 did not. Connect the light switch to a good ground with a jumper wire and press the brake pedal. The brake lights turn signals reverse lights all work but the tail lights when you head lights are on do not work. I have changed the bulbs fuses checked the tail light circut board checked the headlight switch.

Burnt out light bulbs the other reason your tail lights are not working but your headlights are maybe a blown bulb. Electrical is not my strong point so any help would be. If it does not light up then replace the fuse with another of the similar amperage and size. When i checked the wires at the tail light only the wire that worked the turn signals had juice the other 3 did not.

If the tester lights up your fuse is functioning fine. If the brake light turns on you have to fix the ground connection. In many instances you can see the break in the metal strip of the fuse. It could happen due to a loose connection of the wire or the corrosion or damage of the wire ends.

Its got to be a fuse if not i guess it could potentially be a bad relay somewhere in the vehicle. I have changed the bulbs fuses checked the tail light circut board checked the headlight switch. I would second check the fuses probably the best to start especially since its just the rear cause they are probably on the same circuit.