I was informed that my right rear brake light was not working. OK, I'll just replace the bulb. Replaced the bulb (the one with two filaments). Rechecked the brake lights, no good. Must be a bad replacement bulb. Replaced with another new bulb. Still no good. Must be the fuse. Checked the fuse, it was good. Must be the bulb socket, checked that; it was good. The left rear and center brake lights works when the brakes are applied. All three works when the park light is turned on. Checked the wiring harness with a test light...the park light works and the brake light doesn't. Do I have an open wire somewhere? Any ideas? Will the dealer fix this under warranty?

 

As long as you haven't done anything that could be considered altering the wiring, then I should think they will fix it.

 

Take the car in. You really need a wiring diagram and a multimeter to troubleshoot this circuit correctly.