I have just put a new heater core in my 735,while I was testing it to see if it was all working ok I noticed that when I used the blower switches,a relay that sits loose near the heater controls gets very hot & also the wires leading to it.This happens with all the heater switches,except when I use the Defrost switch. Please can anyone tell me if this is normal,or where the problem might be. Thanks in advance Tony