1999 Buick LeSabre keeps blowing fuses for the tail lights. Fuse - and lights - may be fine for a week, or may blow in an hour. I see no problems in the harness near the lamps. One person suggested a problem with the system that automatically turns lights on at dark, another wondered if running phone charger from lighter could be an issue. I have no wiring diagram and local library does not carry car manuals. Suggestions?

fuses blow because of dead shorts or excess current draw
to blow a 15 amp fuse indicates a dead short
by disconnecting the rear lights , the problem is in something else you have replaced
could be a problem in the head light wiring

You may have a damaged wire leading to one of the lights that keeps blowing.
Not fun, but you have to chase down the wiring to everything that keeps blowing out.

The fuse is blowing because there is a short to ground in the circuit.
It also includes the parking lights in the front of the car.
The sockets and wiring will need to be checked for shorts.

the dash and tail lights are ran on the same fuse/curcit your shorting to ground somewhere along the lines. check for a broken bulb melted wiring or a broken wire

depends on what is wrong.first check fuses. fuse box should be under dash on left hand side. may also be a fuse box underhood. check all fuses with a test lamp. replace any blown or open fuses. if tail lamp fuse is open and blows again you will need to trace wirng harness to find cause of short. check in rear of vehicle. remove tail lamp asm to see if any wires have been pinched or shorted to ground under the mounting bolts.(common problem) .good luck

Try removing 1 bulb at a time and see which one stops the fuse blowing .You could have a faultyb bulb I saw it before.

Tail lights OK too or are they blown. Could be centry lights working and no tail or running lights. Trace wires out of column to check for arc and also check wires at taillights, sometimes wires get damaged back there.

disconnect the visor map light/vanity lights (at the connector) one at a time, the short should go away.

I hate to tell you this but its going to be a tough issue to find. You will need to check all the light bulbs are the correct bulb. Make sure they are correct not what was in there. I would check the brake switch on the brake pedal to make sure it is ok. then you will need to trace all the wires to find the short.