replaced fan motor and core and now.....
OK here is the deal..... I have a good ground. I have power in the wire that comes hot when the heat is turned on. The switch is operating. I have power at the three wire connector that goes to the resistor. But, when I hook it all up nothing. If I just jump from the hot when heat is on and to ground the fan blows on high, but nothing when it is all hooked up...........I am pulling my hair out here!! ( what little is left!) What kind of readings should I get on the resistor to see if it is good or bad????? It seems that this can be the only thing left to mess me up. unless I am hooking something up wrong.
I should have the three wire connector which is a no brainer and the hot that comes on when the heat is on........correct????
This resistor is a dealer item and I just don't have time now to scrounge in the yards. Besides, 73-79's w/air are rare in the yards here!
HELP!!
Thanks!!!

Chris

1978 F150 SC 351 C6 $1000
Soon to be Bronc owner!!
1969 Buick LeSabre 400
1941 Farmall "A"

 

Your resistor stack is bad. You have in-as-much said so yourself. A bad resistor stack will get an infinite (open) reading. Also, the resistor coils are probably good. It is the single ceramic electronic resister that is probably bad. If you knew the rating of that little one, you could solder in a new one for 5 cents. Test each resistor individually and you will see what I mean about the little one being bad.