We can not find any wires coming out of the blower housing. This again is a 1973 F 150. My son sent a couple pictures and am going to send them to you to see if you may be able to identify some wires that we could test from.

Thanks
Larry

PS Was not sure how to send pictures so I think you got the same ones twice.
[IMG]https://cimg7.ibsrv.net/gimg/www.f150forum.com-vbulletin/640x480/80-img_2297_0702e424fc8d121da0e1dec2b410209dcf3a633c. jpg[/IMG]



PIcture #1



Picture #2

 

There were 2 different setups/diagrams that I posted. Yours looks like version 1 (blower motor in engine compartment) rather than version 2 (blower motor behind dash).

I was suggesting the power wires could be these since the business end of the motor is on this side of the squirrel cage.

Possible blower motor relay?



But then looking at the diagram suggests that the wires are in a different location:


Diagram suggests it is located here...

:

 

Yeah that's not the blower motor relay on the fender. Your truck has AC and the blower is in the engine compartment. The ones with the blower motor inside the truck is non-ac. I'm not sure where the wiring is exactly though as I don't have AC.


I understand that you're trying to diagnose this from afar, but be more specific. What are the problems? Blower isn't working at all? Blower only works on high speed? Blower makes god-awful noises?


You can pull the blower motor out from the engine side as shown in one of the diagrams and there will be 2 wires connected to it. 1 power, 1 ground (usually orange power and black ground). Connect 1 to positive and 1 to negative and see if it works.


A new blower motor isn't expensive and a blower wheel isn't either. I'd just replace both while you're in there.