A/C Wiring Help!!!!

[jmartin99]

I am putting together a '72 Challenger for a friend that was in boxes when I got it. I am trying to connect all of the wiring in the engine compartment and front lights. I was given new wiring harnesses for the engine and front lights.

The problem I have right now is I have no idea where the wiring for the A/C comes from. There is the two wires off of the sensor on the right firewall and the wire that controls the compressor clutch. I have no idea what connects to these. 

Also, there was a new relay part number 19913, that googles as an A/C Relay, I have no idea if it is even supposed to be installed on this car and if so where does it go and what wires hook to it? 

Thanks for you help with this!!!

Jeff 

[FY1Cuda]

Here's what I have for a '70.  Shows the relay behind the glove box.

[1 Wild R/T]

I don't know 72 wiring but in 70 the A/C clutch lead and blower motor lead both enter the engine compartment at the bulkhead connector, they tag into the four wire connector that also has the reverse light wiring...

I suspect the sensor on the firewall you mentioned is emissions related, Chrysler called an OSAC valve.. 

A cut & paste....
The OSAC valve has been used since the early 1970s to delay the distibutor's vacuum advance for about 15 seconds during acceleration. The OSAC valve is on the air cleaner (pre-1974 models had it on the firewall!) . One hose runs from the vacuum of the distributor to the valve, the other from the valve to the carb. Running the hose from straight past the valve will eliminate its limitations, and compensate for a bad valve.

[swede-cuda]

  relay. dont Think there should be one. 

[ShelbyDogg]

All of my original A/C harnesses have an add-on harness under the dash, that plugs into the main harness, heater controls and resistor bank? Do you get one of these?

[jmartin99]

He gave me a "Rats nest" of all of the original wiring from the car, actually two cars I believe because he also had a donor car for the A/C stuff, so I may have the original harness. Can anyone tell me what I am looking for? What color are the wires and what the connectors look like? That would be a big help!

Thanks! 

Jeff

[CHL2T]

My 70 AC wiring is dark green, light green, black and brown. The switch connector is red.....

[jmartin99]

I found this in my shop manual...



It says the Dark Green wire that goes from terminal 4 on the bulkhead connector to the Air Conditioning Motor...does that mean the blower motor?

There is also a blue wire that comes out of terminal three of the same bulkhead connector, Does this wire go around to the pressure sensor on the accumulator?

I am still trying to figure where all of these wires go and what I still need to get hooked up.

Thanks! 

Jeff

[ShelbyDogg]

Yes and yes. Blue goes to drier low pressure switch, then on to the compressor. Green goes to blower motor.

The 2 single wires that plug on to the a/c-heat control switch are what power that blue wire when "max A/C' or "A/C" is depressed.
It doesn't matter which one is plugged up or down, the switch just connects them together to energize the comp clutch coil.

[ShelbyDogg]

We troubleshooted a guy's A/C blower and compressor wiring in this thread:

http://www.cuda-challenger.com/cc/index.php?topic=65095.15