Camaro tail lights

i have a problem here. my tail lights and dash lights dont work on my 1991 camaro. the brake lights works but the tail lights wont works and the tail light fuse runs the dash lights and the tail lights. anybody have any idea what can cause this?

Assuming you have checked the obvious culprits like fuses and checked for power and ground issues at the taillights, a prime suspect would be the headlight switch/rheostat.

the fuse keeps blowing when i put a new one in. and i know its not the bulbs because the brake lights work

It’s probably time to start physically inspecting the wiring for damage or a short circuit. Wiring for the taillights will probably be easiest to inspect, so start there. Check for rodent damage, melted insulation, chafing, etc and repair as needed. Also check for a proper ground. A poor ground can cause excess current draw, resulting in blown fuses. It’s also possible to have a short in the bulb sockets, so carefully inspect those as well.

Though the brake lights and the tail lights may share a common bulb in the rear they are seperate circuits and use different filaments inside the bulb and have seperate fuses. If you have a trailer harness installed on the car that is a common source of trouble. If the radio has been changed out that is another suspect area to check.

Just a note on the statement about a poor ground. A circuit with a poor ground will actually have less current flow through it, not more, because a bad ground connection increases the resistance of that circuit. When a fuse blows out it is usually due to a power wire making contact to a ground point somehow. When that happens current flow will be very high due to the very low resistance in the circuit. If not for the fuse the wire would burn up due to the excessively high current flow.

Check to see if the parking lights in the front work when the dash lights and tail lights don’t work as these might be on the same fuse. If the parking lights do work (not the turning signals), then you don’t have to check for the short in the front of the car. Also check to see whether or not the license plate light illuminates. If it is on the same circuit, here is another place to check.

I would start by removing the exterior bulbs affected by this circuit and then put in the correct size fuse and see if it blows. If it doesn’t, then you have a problem with one of the bulbs or the way it was inserted in the socket. If the fuse does blow, then check for a chafed wire. Another post suggested the rheostat that dims the dash lights. If you can disconnect the rheostat, try a fuse and see what happens.

I had this happen on my 89 camaro 5 years ago. IF I REMEMBER RIGHT, I think it was a relay behind the dash in the middle. it went out because of a wire had shorted behind the dash. I will have to look when I get home to see if I have any of the documentation from the shop that found it.

hope this helps.