A/C clutch 12V wire info

[dank1945]

Hi,
Can anyone tell me which of the two, black or white, wires going to the A/C clutch is the 12V?, from the diagrams? (1994 F350 IDI)

I need to connect my newly installed electric fans to the +12V so they'll come on when the A/C is turned on.
Thanks in advance,
Dan

 

[geonc]

By doing that alone------ those fans will be running constantly as long as you run the air conditioner....not needed at road speeds---- and will randomly cycle when you are in defrost mode because the clutch cycles even then!

Don't see any truck info in your sig to offer any suggestions about using the FIPL switch if you have an auto

And right now my CRS prevents me from telling you what wire....

Just run a toggle to the relay for now to get going

 

[dank1945]

Hi Geonc,
Thanks for the response. I do have a manual switch rigged up, mine is a 94 F350CC 7.3L IDI.
The kit from AutoZone comes with a green wire that's supposed to be hooked up to the 12V in the A/C clutch so the fans will run whenenver the ac is on.
Dan

 

[RLDSL]

Hi Geonc,
Thanks for the response. I do have a manual switch rigged up, mine is a 94 F350CC 7.3L IDI.
The kit from AutoZone comes with a green wire that's supposed to be hooked up to the 12V in the A/C clutch so the fans will run whenenver the ac is on.
Dan

Take a volt meter and turn the ac on and unplug the connector from the switch at the accumulator. then check the wires. one of the 2 will have 12v . tap your fan relay into the other wire, that way it will be switched to go on with the compressor.

 

[dank1945]

Hi RLDSL,
Thanks for your reply. Could you clarify where is the "accumulator", and confirm that I should tap into the other wire, not the 12V?
Thanks,
Dan

 

[RLDSL]

Hi RLDSL,
Thanks for your reply. Could you clarify where is the "accumulator", and confirm that I should tap into the other wire, not the 12V?
Thanks,
Dan

The accumulator is the upright canister attached to the evaporator housing ( the place where the inside blower is hiding and where the heater hoses go in) follow the AC line from the front of the truck at the condenser ( the thingy in front of the radiator that you are trying to rig a fan on) on the passenger side, it goes straight back to the evaporator, the line comes out of the evaporator and goes into the accumulator. the sswitch is on the side of the accumulator pointing toward the fender.
Yes, you want to use the wire that does not have 12 v going to it when the plug is disconnected and the ac turned on , to trigger the fan relay, that way the fan will only turn on when the ac compressor turns on. If you attach it to the other wire, the fan will be on all the time when you turn the ac on. You only want it running when the compressor is running to reduce the head pressure and make it run colder.

 

[dank1945]

Hi RLDSL
I'm very grateful for your reply. I don't think I'll have any problem doing that. My ac doesn't blow cold, so I purchased a can of sealant and a couple of refrigerant to try and fix it if it's a slow leak. Any words of wisdom? I haven't read the instructions yet.
It sounds like yours is the kind of truck one would want to get a hold of! I can't believe all the stuff that you've done to it. I'm just trying to sort mine out to be able to go reliably anywhere with it... which I thought I had until the fan fell off last Friday, chewing up the 3 month old rad ($440 Cad).

Cheers!
Dan

 

[subway]

if your truck is a 84 and up it should be the black with a yellow tracer (most likely), or a gray with a white tracer according to my manual. all the years i checked through were the same color at the compressor clutch itself.

 

[Mat J]

why not get a temp switch for ele fans from jegs or summitracing.com This way your fans would come on when you need them on not just when the ac is on.

 

[cm1hedge]

My ac doesn't blow cold, so I purchased a can of sealant and a couple of refrigerant to try and fix it if it's a slow leak. Any words of wisdom? I haven't read the instructions yet.
Dan

I would steer clear of A/C sealants. They tear up compressors and don't make A/C techs very happy. Sealants will destroy recovery machines. Get some UV dye and locate the leak.

 

[geonc]

why not get a temp switch for ele fans from jegs or summitracing.com This way your fans would come on when you need them on not just when the ac is on.

fans are needed when idling with ac on---gotta move air across the condensor or the pressure builds and blows stuff up
{don't ask how I know}

 

[Mat J]

ah ok well you would still need a temp switch for the engine temp instead of using a manual switch. and also run a trigger wire for a relay with the blower 12v.