After my AC runs for awhile (30-45 min or so) Wen the Fan is on 3 or 4 it cuts off. I kow the are on two seperate relays, one for 3 and one for 4. Whatis causing this...is it that they are over heating? Do they need to be replaced? (Should I swap them with one of the other relays like the high or low beam and try that first?) Unfortunately I am never in a position to check them out when the fan stops. Michael Vin# 2944