I'm in the middle of adding AC to a truck that didnt have it. The truck has been re-wired, so it's not just stock plug 'n play. From the junk yard, I grabbed all the wiring pigtails that I could and I THINK I got it all. But I'm having a little confusion with the resistor wiring.

I've been following the wiring diagrams posted up at Fordification.

Here's a picture of what I have:



So where the confusion lies is with that unhooked red/black wire. From the diagrams I found, it looks like it AND the other red/black behind it should connect to the orange heater wire, which is what I've done. HOWEVER, when I do that the motor still runs very, very slowly with everything in the "Off," position. With that single red/black wire pulled like it is in the picture, everything SEEMS to work normally...but I havent quite gotten to wiring up the 3 wires that come out of the back of the control slider yet, so maybe that will clear things up?

Can someone point out what I'm missing?

I've found reference to relays for the blower in a few posts, but I didnt see any in the junk yard and I dont see one referenced in the diagram I posted a link to.

 

One of the red/black wires comes directly from the fuse box and has power on it with the key in run. I don't know which one you are unhooking, but make sure that one has no power with the key off.

 

As far as I can tell from the pinout linked, they both branch off of the orange heater wire; it's hot in the "Run," position, but off in the off position.

 

Ok, maybe I looked at the diagram a little too quickly. I thought that c-606 was a "either/or" thing, but it's just a plain connector correct?

If that's so, then what you are saying is the power 181 orange wire goes over to the far right, through the dash selector. The fan circuit gets power in any position except position #1, and the A/C clutch gets power only in position #3.

So I would find the proper red/black wire coming from the dash switch and see if it has power on it with the dash switch in the off position. In off this should kill the whole thing correct? I would get a voltmeter or testlight and check it out.