I have a 1998 4 door vw jetta 2.0 liter in which the AC, Fan, and rear defroster will intermittingly not turn on if the car has setting for a while. Furthermore, when this happens, the brake light turns on. If I run the car for a couple of minutes, turn it off, then restart it, the problem dissapears. Any thoughts?
I would guess these things are tied to a common power source somewhere, possibly a breaker, fuse, or relay. There seems to be a intermittent power connection causing this problem.
I suggest you purchase a service manual to help you find the trouble area. It will save you money and time if you can repair things like this yourself.