I, of all people, have a wiring question for those of you who have a 240Z with A/C.

I'm rebuilding an engine harness and I'm going to ADD in the A/C controll wire. The questions are these.

1) what size is the blue control wire? 14 gauge or 16 gauge wire.

2) does the A/C pump only go on the left side of the engine compartment or is there a passenger side A/C pump? And if so, does it also only require a single activation wire?

I can't find any good pictures or threads that describe the wire, size and location and where it goes other than into the firewall into the passenger side. I've seen the thermostat switches IN a Z before but never followed the wires.

Any help would be greatly appreciated, not only by me, but my customers and all of you who, in the future, decide to have me rebuild your engine harness and add A/C into the harness.

Post here or write me directly at wolfin32z@yahoo.com

Thanks in advance,

Dave

I have a 280 w/aftermarket AC. The blue wire on mine is 14ga. I have seen compressors mounted on either side of the engine compartment on the 240Z aftermarket systems. There are two terminals on the thermostat switch. One draws the power from the switch that turns on the heater fan. The other goes to the switch on the compressor clutch. I don't think it matters which terminal which wire is on since it just passes the signal through. Which side the wire goes through the firewall on depends on which side the compressor is mounted on.

Regarding the location of the compressor it is my understanding that back in the day it would have been most common to have the compressor mounted on the right side on a bracket that obscures the fuel pump. Compressors mounted on the left side tend to replace the original air pump; I doubt that dealers would have removed that.

My "factory" A/C was mounted on the driver side above the smog pump. (York compressor) It had a single hot wire to the clutch.

I'm still waiting for the customer to figure out which Compressor he wants but I guess I could run a wire to both sides of the engine compartment.

But as long as it's just a contact or activation wire then it should be no big deal to run it to both sides. If it were a power wire, that actually carried amperage, then it would be a whole different story. Larger guage to the passenger side and kick it down a notch as it traveled to the drivers side.

Thanks alot guys, this has been helpful, now I just need him to make up his mind and I can finish this thing. I'll let him "chime in" when he makes up his mind or brags about the harness.

Thanks again,

Dave.

My "factory" A/C was mounted on the driver side above the smog pump. (York compressor) It had a single hot wire to the clutch.

My dealer installed York system by FrigiKing is also installed on the driver side above the smog pump.

As a point of interest, the A/C compressor could be activated by the top heater control lever by being placed from "Vent" to "Off". This was accomplished by a micro switch being activated at the end of this cable under the passenger side when the vent door is closed. As long as the A/C

thermostat control rotary switch was out of the off position, the A/C could be turned on and off by sliding the top vent control to "OFF" or "Vent".

Since my car was restored, and this was never reconnected, I have been search for the dealer wiring diagram for this install so I can reconnect this micro switch correctly, again.

If anyone has this diagram or knowledge as to how to correctly hook up this micro switch, It would be a big help to me and may assist Dave with his install. Thanks.

Dan

I have the original ara manual but it is not very helpful

What Dan says is also true on my car. The compressor will only come on with the top lever in the Off or Vent position, with the fan lever on at any speed, and the rotary control out of the off position. I had to change out the control panel once but I didn't note how it was set up. I just plugged everything back in as it was before.

actually Steve (Madkaw) that diagram is very useful. It shows a 10 amp fuse and that lets me know that the 14 gauge wire will be sufficiant for the activation wire I plan to run.

Thanks guys.

Dave.

actually Steve (Madkaw) that diagram is very useful. It shows a 10 amp fuse and that lets me know that the 14 gauge wire will be sufficiant for the activation wire I plan to run.

Thanks guys.

Dave.

So, Dave, I am really stupid when it comes to electrics and reading wire diagrams, but it appears that in madkaw's diagram the power source for the compressor is the heater control switch and the toggle switch shown in his diagram could very well be my micro switch which is opened and closed by my vent control slide lever. Does this sound correct to you?

I may be getting closer to my answers.

Dan

I have the original ara manual but it is not very helpful

Steve,

Were there any more pages to that ARA manual? I would love to see, or get a copy of your manual if that would be possible.

Dan

Dave and all----

I'm the laggard that "Electrical Hero" Dave mentioned in the post above.

Thanks to all of you that contributed to his thread to help answer his question.

I have decided that running the wire to the driver's side would be best since it appears that the A/C compressor and clutch have been mounted there regardless of which style of compressor was used. (early piston York or later rotary Sandlin)

Does anyone have pictures which show the mounting of these types?

I have access to a complete York unit, but it is mounted to the passenger side. Will the bracket simply reverse for the driver's side?

I understand that the rotary type Sandlin compressors are more efficient and more reliable, and as such I am leaning toward using it.

Any thoughts and opinions from ya'll concerning the pros and cons of these installations are much appreciated!

Thanks again.

Jim D.

"Zup"