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Anyone redo the factory AC wiring? I'm working with cut leads from either PO or rodents. The rest of the truck I rewired with American Autowire's classic update series (which I deeply regret doing) and does have an AC/heater lead but trying to figure out how the AC unit is wired with it's own harness.
I have a couple harnesses from the parts yard from similar year dent side trucks with factory AC cause mine's cut up, but they're 1976+ since its a D6TB-19A885-C harness so I'm not sure it works with my unit even though they look very similar. What I have left from the original wiring is in the picture I'm not sure where that grey or white lead goes to, and on the engine bay side everything is cut except for the single black lead to the compressor.
1973 F250 4x4 Ranger XLT
(I have OEM AC, not dealer added)
What ignition system do you have ? Points or Dur Spark system ? The 76 and newer stuff will have a wire that controls idle rpm if the A/C is on at idle so as to not stall the motor because of the A/C load. The engine compartment A/C wiring has only the A/C compressor clutch switch and one other connection which the name of at the moment evades me. It won't be to hard to figure out. Give me a bit and I'll see what I can come up with. There is one vacuum hose that comes from a vacuum tree on top of intake manifold to a vacuum reservoir/reserve canister then through the firewall and supplies your A/C vacuum switches under the dash.
Full MSD billet dizzy with CD box and American Autowire harness. Well maybe I can just eliminate a wire from that 76 harness, it's very clean and complete.
Full MSD billet dizzy with CD box and American Autowire harness. Well maybe I can just eliminate a wire from that 76 harness, it's very clean and complete.
The '73 & '74 have an ambient temp sensor on the front core support. The '76 doesn't have this. It was wired into the compressor clutch circuit.
Crap looks like I’m missing mine and will have to locate one. I’m just realizing that the wires are different colors to the ‘74 schematics as well and Fordification does not have any 1973 diagrams.
Also, I have the service manual set. All 5 volumes and not a single wiring diagram! My Hayes only has 74-78 and 79!
Does anyone know where the Orange cable goes to that comes out of the AC controls connector?
My truck's blower motor power wire is black w/yellow stripe and today I got that working with the different speeds (finally a win!). The AC control switch has the orange wire coming out so maybe its the color that the AC uses for power on my truck.
I'm definitely missing the ambient sensor on the radiator support. Anyone have a part number for it?
One of the wires on that same harness is white with a grey connector and I'm wondering if it's for the ambient temp sensor.
I'm definitely missing the ambient sensor on the radiator support. Anyone have a part number for it?
Ford P/N D0VY-19618-A
Motorcraft YH-121
The switch is shown on the schematic that redroad posted in location D/E 44
There are five switches listed on ebay right now from $47 to $79.
I have a factory A/C in my 74... what do you need? I have plenty of pics.
I left all of my stock wiring intact and had to rebuild the switches behind the dash... but it is all there and functioning.
Here: The purple wire in your first pic goes to the ambient temp sensor on your radiator support. The black wire from the ambient switch goes to your clutch on the front of the compressor.
The black wire with the ring connector goes to a ground source, the other plug I don't know... ONLY the purple and black are AC related out of the harness in the engine compartment AND one orange that hooks to a black 10 gauge wire above the HVAC box. That's it... everything else is under the dash. Gimme a minute and I will get some more pictures.
Crap looks like I’m missing mine and will have to locate one. I’m just realizing that the wires are different colors to the ‘74 schematics as well and Fordification does not have any 1973 diagrams.
Also, I have the service manual set. All 5 volumes and not a single wiring diagram! My Hayes only has 74-78 and 79!
Does anyone know where the Orange cable goes to that comes out of the AC controls connector?
yeah and something else the service manuals don't have are vacuum diagrams.
The orange wire that comes out of the mode switch should plug into the power wire that goes to the fuse panel.
Look at the diagram redroad posted, the diagram shows both heater only and fact a/c wiring. Ignore the wiring to the right, that's heater only. In the diagram you can see the orange wire runs from the mode switch go fused power. It's at the top of the diagram.
Thanks for the part numbers Mike! Searching that part number led me to another one of Flecker's posts with a helpful picture of the switch!
I do have a vacuum diagram luckily (oddly enough its in the electrical volume of the manuals, despite not having any wiring diagrams)
