the number 2 fan in my daughters lumina will not run, in traffic the temp light comes on. I've powered the fan manual and it runs, I've changed the relays with no effect, changed the heat sensor? at the bottom of the thermostat housing with no effect, can anyone tell me where else to look? and the book mentions the a/c head pressure switch, can anyone tell me where that is located on 3.1 lumina 94 model? thanks for any and all help.