so i started my car and tried to turn the heat on to defrost the windows and nothing came on and my radio shut off. if i turn the fan off radio comes back on and if i try and turn it back on radio cuts off and still no heat or anything. never had a problem with the blower motor or anything before. i checked the fused and replaced the resistor thing on the blower housing and nothing. im stuck on ideas. it must be electrical but i know nothing about that