in my 02 Yukon Denali..The front heater blower keeps Turning on and Off on its own..I mean it will work for a Bit and then stop working..anda few minutes later..it would work again...Is it the blower motor thats going or can it be the resistor or something else...Sucks when you are driving down the road and the front windshield starts to fog up...any help ya can give me would be awesome