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Need Info on A/C Relays


Active Member
May 14, 2016
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Speedway, IN
Morning, Lets see if I can explain this in one shot. I have my 1980 D150 318 4 speed. I am in the process of hooking the A/C back up. I have everything needed to do so, except. on the drivers side inner fender, I have two 3 prong plugs which I believe need relays to work the A/C properly. These are 3 pin female inline.

I can't seem to find these relays, or anyone that knows if they are needed to run the A/C. I have not evacuated the system and filled with 134a yet. I am not at that point. I am using my original RV2 compressor and have the necessary parts to convert it. I have checked the clutch and it's working fine.

So my question to you is do any of you have these relays laying around or know where I can get them or what I can use to replace them with. How to test to see what connection does what is another concern. Is there a schematic for the A/C wiring as to what each pin goes to? This is why I was just hoping to be able to plug in some relays and be done with it.
Thanks guys and gals, Larry