Putting AC in Non-AC Ranger Switch Question

[CatBee]

I have a 1993 Ranger XL with the 4.0. My truck is a factory non-ac truck and so far I've gotten or ordered everything I need to do the conversion to AC. I've got the box, compressor, lines, condenser, evap core, factory ac control panel, all of it. My truck does have the mounting point for the compressor, the bracket is there complete with bolt holes, my fuse box in the engine bay has pins for the WOT relay, and my truck had all of the fog light wiring already there too, so I'm assuming it already has all of the ac wiring. However, I had a look in the engine bay looking for the 3 plugs for the switches and compressor and I couldn't find them. I found one blanked off plug maybe near the fusebox on the driver side but it isn't nearly long enough to reach the AC stuff. Could the rectangular plugs for the compressor and switches be hiding in the looms somewhere or does my truck just not have them?

 

[Uncle Gump]

@RobbieD I know you use to do some add on A/C back in the day... any help you can offer?

 

[Roert42]

@Curious Hound

I think you at some point installed and then removed the AC from your 3.0 truck?

 

[Curious Hound]

@Curious Hound

I think you at some point installed and then removed the AC from your 3.0 truck?

My truck originally had AC and I removed it. If your truck was originally built withput AC, it likely jas some of the wiring. But may not have everything. I may be able to get pictures of the connectors for you, if that would help. But, if you don't have parts of the harness, you will need to get it from a junk yard or spurce the connectors online and build the harness. I can post photos from the wiring diagrams if you need that.

 

[RobbieD]

I know you use to do some add on A/C back in the day... any help you can offer?

I can't say for certain. I have a '94, but it's factory AC. I did do a lot of aftermarket, and a fair amount of OEM AC, but that was late '70s through the 80s. Early imports were generally prewired, and easy to add AC, but domestics sucked doing OEM kits, because of how much stuff that had to changed out, on top of the AC components to be installed.

I think that by the mid-90s, Detroit had finally gotten the memo, and started making things somewhat easier. The "fair amount of OEM" installs that I got to do, were from car dealerships paying my aftermarket shop to put their OEM AC kits in their vehicles; their mechanics hated doing them, it was such a pain in the ass.

My truck does have the mounting point for the compressor, the bracket is there complete with bolt holes, my fuse box in the engine bay has pins for the WOT relay

That's a very good sign, especially if the socket is populated with terminals. The compressor mount being there is also very good.

My "best guess" is your truck may be partially wired.

I found one blanked off plug maybe near the fusebox on the driver side but it isn't nearly long enough to reach the AC stuff. Could the rectangular plugs for the compressor and switches be hiding in the looms somewhere or does my truck just not have them?

Hopefully, the one plug that you have found is C113 (see the 1993 diagrams that I include below), which will need an extension harness to go to the compressor, that will also include the AC diode. If this is the case, I'd get the short harness from a junkyard donor.

The other connector that I hope is in the truck already, is C167, for the pressure switch. Look around the passenger rear corner, for an unused loose connector, or an unused one that's taped off to a harness.

I suspect that you're OK on the inside switch wiring, and I suspect that the existing PCM is already wired and will work like it's supposed to.

Use wire colors on these diagrams, and the locator view, to help you in trying find those two engine bay connectors.

Good luck!

,

 

[CatBee]

So I took some pictures in the engine bay and interior. The driver side had all of the plugs pictured, I'm guessing the rectangular one is the one for the AC extension harness? Correct me if I'm wrong. Also I looked in the passenger side and didn't see any loose connectors from what I could see. I didn't get really digging because it's raining atm. I also took a picture if the fuse box showing the populated pins for the WOT relay and under the dash where the vacuum actuator for the recirc/ambient air flap is present and, until a couple of days ago, wasn't hooked up to any vacuum lines.

 

[RobbieD]

Wire colors at suspect plugs will tell you the most.

C113 should have a Black / Yellow wire, and a Black wire.

C167 should have a Pink wire, and a Dark Green / Orange wire.


The rectangular connector in your picture #2 looks like a shorting plug to me, like the one used to set the timing.

Unfortunately, the 1993 EVTM does not show C113 and C167 as connector views, which would hint at their shape.

 

[Curious Hound]

The rectangular connector in your picture #2 looks like a shorting plug to me, like the one used to set the timing.

That may be the diode at the compressor.

 

[CatBee]

I did some more digging today. None of the driver side plugs matched the wire colors you gave me and the passenger side seemingly has no plug. I felt the loom and I didn't seem to feel any hardness like a plug hiding under the loom so I'm beginning to think I so not have the wiring. What should I do?

 

[Curious Hound]

I did some more digging today. None of the driver side plugs matched the wire colors you gave me and the passenger side seemingly has no plug. I felt the loom and I didn't seem to feel any hardness like a plug hiding under the loom so I'm beginning to think I so not have the wiring. What should I do?

Get the stuff from the junk yard. It's time consuming. Or, at least get all the connectors with long pigtails so you can buy wire and make your own harness.

 

[CatBee]

I think I'll just make my own harness. Im no stranger to wiring things and from what I've looked at thus far all the ECU does is the WOT cutoff which I could very well just bypass. Just wire the button in the cabin up with the switches and be done with it.

 

[SenorNoob]

Can you get all of the connectors new?

 

[CatBee]

If I'm not mistaken from looking at them they are all the same rectangle style connector and I have seen them for sale as new pig tails so I should be able to.

 

[RobbieD]

If the truck lacks the proper wiring, I'd also just add what's needed to make the AC run.

The schematics I posted should get you there, and I agree that the WOT relay probably isn't needed.

In case it helps, here's the EVTM description of how the stock AC circuit operates with WOT relay:

For what it's worth, some the old AC kits that I used to install would include an "idle-up solenoid", which would kick the throttle linkage a hair up when the AC clutch was engaged (most engines back then were carbureted). I don't know if you'll run into that with the bigger 4.0, or, if the PCM will automatically accommodate and adjust the idle with the compressor's load.

Still, if the plugs ain't there, I'd approach it as adding the OEM components, and then wiring it independently.

 

[SenorNoob]

4.0 SHOULD correct idle speed for any load with the IAC.

WOT cutout was necessary for that little extra bit of umph when you didn't really have enough power anyway. I know I had a 92 w 2.3 that something didn't work right so I had to turn the clutch off manually leaving a stop if it was uphill to keep from stalling.