Brake lights not working with headlights on?

2000 Jeep Grand Cherokee brake lights not working...?

• I have a 2000 Jeep Grand Cherokee and one day a friend noticed that my driver's side brake light was not working. So, I replaced the bulb even though I noticed that the current bulb was not burnt out or anything. After putting in the new bulb, the brake light still did not work. However, the passenger's side brake and the liftgate brake light both still lit up when the brake was pushed. I tried taking the bulb from the passenger's side and replacing it on the driver's side. Still nothing. However, after a couple more tests (pushing on the brake to check for the light to light up) the passenger side light and the liftgate light failed. Now none of my brake lights work. However, when I turn my headlights on, the brakes lights do light up, but do not get brighter when the brake is pushed. Does anyone know what may be going on? I am completely baffled... Thanks for any and all help!!

• Answer:

  I would look at your grounds. A fuse does not work on "individual" lights they protect the whole circuit, for example both tail lights. If you get a Hayne's manual it has a wiring diagram in the back section and it should help you trace the ground, most likely the cause of your problem. I have a 97 Grand Cherokee so I don't want to give you the color codes as they might be different. All you'll need it a screwdriver, Multi-meter and patients.