I have a decent amount of knowledge about cars, so I always try to fix things myself before taking it to the shop. This problem, however, has me absolutely stumped. Here it is:

When I turn my car on and pump my brakes, the lights work two or three times and on the final pump it gradually fades out(I can also feel the resistance on my pedal stiffening up at the same time). The weird thing about it is that my 3rd brake light always works, even when the main two do not. No fading, not dimmer...works just as it should.

So far I've checked fuses and relays and searched for exposed wires(only from the trunk to the rear seat so far) possibly shorting it out but have come up with nothing. Has anyone experienced this or know a good starting point to begin my searching?

No ideas or suggestions from anyone? Come on gurus, lets get some input!!