Re: heater core trouble
I had the same prob... it is a intermintnent problem,(my cd player not working) but the hissing is your vent valve(the thingy that chooser defrost, vent, floor ect.ect.) You hear a hissing from the floor under the dash in the driver side compartment. I have not had the time to chase exactly where it is, but if you find it you will have a pair of greatful ears on this side of the screen.
I have no idea about the elecrical prob, mine only happens when its really cold.
does your cigrette lighter work? if it does your prob is in the stereo itself of not its the electriacal system itself, Also, check your blower fan is plugged in correctly and is working... Thats all I can think of Right now I let you know if I think of anything else.
Like A Rock