My ac compressor and fan turns on for a sec. when u start the car then shuts off. I have checked the wires, the freon level, relays and they are all good but still wont work. I took it to a mechanic and they traced all the wires and checked the grounds and they said it was all good too. Can sumbody plz help i leave for school in 5 days and really need these fixed.

i forgot to say it was the cooling fan that shuts off