brake lights dont work when headlights on 2001 jeep

Answer 1

In order to diagnose the problem you must check several possible problems:

1) Check your bulbs, if they are new, move on to 2)

2) Check the fuse box, if it is in good shape then that isnt the problem

3) Check the brake switch, you can test this by checking your third brake light in order to see if any current is being passed

4) Check the wiring that connects the brake system to the brake switch to the directional switch then back to the brake lights; if directional switch functions but brake lights dont the problem can be the directional or blinker lever switch.