Adding A/C but need wiring help

[DonovanJM]

Well things are looking good. Not only do I have the ac relay plug and connectors I have the actual relay and fuse. Seems kinda weird that they are there but they are. It also appears that I have the violet wire at pin 41. So hopefully once I get everything it will fire right up!

 

[RonD]

Looking Good

Check for black/yellow wire from PCM pin 86, that's the ground from the AC pressure switches
Also a grey/white wire that comes from AC relay(pin 4) and goes to compressor
Those are the only 2 wires that would attach to the added AC parts

The pressure switches just have a ground to body/engine same for AC compressor clutch, so those wires can be added or will be attached to used parts

 

[DonovanJM]

Finally got around to looking for those two wires. I definitely have black/yellow at pin 86. Not sure about the gray/white wire from the relay. I couldn't figure out out to look at the back of the relay. I did find that there is a gray/white wire at pin 6 on the connector under the brake booster.

 

[RonD]

The grey/white wire would be in the engine wiring harness as it runs from relay to AC Compressor, not to firewall

You could use an OHM meter to test slot in relay and test if its connected to the grey/white wire
(you can use a sewing needle to pierce a wire to test it, as needed)

Looks like your year is using Micro Relays, slots seen here: http://www.gtsparkplugs.com/images/micro-automotive-relay-wiring.jpg

30 or 87 can be the grey/white wire, Ford has them as 3 and 4 repectively, so "4" should be 87 and the grey/white wire
But 30(3) could be as well it works either way

85 and 86 are 1 and 2, just FYI

 

[DonovanJM]

Just confirmed with my handy dandy multimeter that the gray/white wire is in fact connected to AC relay pin 4(87). I think I'm good to go. Just need to collect the parts. I'm mostly going to get new but I want to grab as much hardware and the wiring harness from a JY truck.

 

[RonD]

Good Stuff

 

[DonovanJM]

Damn this has taken me awhile! Finally got around to getting this done. It works like a champ! My barebones XL now has AC! Next on the list is cruise control. I got the module under the hood installed and I have the buttons ready for install just need to get the clock spring and decide if I am going to install a new brake master now or just do the resistor trick for now.