After suffering for years without AC I decided to hook AC up on my ZENKI S14 SR20DET in my 1995 240sx. The guides I found online were all incomplete and poorly written. I will be flushing this "how to" guide out with pictures when I get a chance to upload them. This install will have all the features the stock ac sr20det ac system like idle bump and functioning triple pressure switch.

First of all, you can use the entire stock KA24DE ac lines and pump. There are a couple "modifications" you will have to make to the lines and pump.

Remove the Powersteering Pump. Use the SR20DET ac mounting bracket, and mount up the compressor. You will find that the pulleys now don’t line up with the pump mounted. The fix for this is to move the pulley on the compressor.

Remove the Front mag clutch of the compressor. This part sucks, but remove the bolt holding the cover. Pry the cover off, then remove the top snap ring. Slide the pulley forward until it lines up with the tension pulley.

You will need a longer bolt to attach the mag clutch now. You need to use washers placed inside the spline of the mag clutch to spacer the clutch out to the proper distance. It should clear the pulley by about 5mm (I'm from Canada and don't get the whole imperial thing).

Now bolt up the lines exactly like stock. Put the belt for the ac on, and plug in the ac mag clutch power wire, located on the driverside framerail.

Bolt up the power steering pump. It may not clear the canister thing on one of the lines. Get out your hammer and bend the cannister down until the p/s pump clears. Bend this gently as it can tear the aluminum.

On to the wiring. You will have to remove the ECU to get to the F3 dash plug.

You now need to jump two wires on the plug. Pin 43-Black Pink (IACV triple pressure switch) and Pin 32 Yellow Black (A/C Thermo Control Amp).

Run a wire from these two jumped wires to pin 46 (Air Conditioning Ac switch output) on the WC ECU. This will tell the ecu that the ac is on.

Now you will have to wire in the fans and the IACV. Go into the Fuse Box and pull out the ac relay. Find the wire running to the ac compressor from the ac relay. Use this wire to switch a relay for the fans.

You will also need to use this wire to send 12v to the IACV AC solenoid. Simply run a wire from the AC relay output wire (the same wire switching the Fans) to the Blue pink wire on the IACV. This will bump the idle when the AC is on.

Now you just need to fill the system with refrigerant, and voila, working AC. Hope this helps.

Nice!! I will be hooking mine up very soon.

Great man! I've been wanting to do this forever, truth be told the wiring scares me. I've got the compressor, condensor, AC lines and belts on just perfect.

Actually I haven't replaced the little tube thing in the middle of the lines (I forgot what it's called...moisture..something?)

But aside from that it's all hooked up.

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The one part of the wiring that confused me was..

Now you will have to wire in the fans and the IACV. Go into the Fuse Box and pull out the ac relay. Find the wire running to the ac compressor from the ac relay. Use this wire to switch a relay for the fans.

You will also need to use this wire to send 12v to the IACV AC solenoid. Simply run a wire from the AC relay output wire (the same wire switching the Fans) to the Blue pink wire on the IACV. This will bump the idle when the AC is on.

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If you could get pictures of this process, that would be a huge huge help .

Thanks! Great write up.

Hell if you're in edmonton I should just road trip it over there with a big case of beer for you .

Kidding. Go Canada!

Go Canada!

I am unfortunately down a digital camera, as I lost mine. I will be adding pictures in a week when I can afford a new one....

But I'll try and explain that last bit.

Basically you need to make sure that the fans come on whenever the ac is on. The stock ecu will control this process with a little more sensitivity, but for my purposes having the fans come on with ac was good enough and more importantly less of a wiring headache.

The fuse box under the hood has the ac relay we are after to get this whole thing to work.

The signal comes from the HVAC control to engage the relay which grounds out at the triple pressure switch. You have 4 wires, one from the HVAC, one to the triple pressure switch, one that gets constant power and finally one that goes to the ac compressor mag clutch. I used this wire to switch a relay to turn the fans on. Basically run the relay inline so that when power goes to the ac clutch battery power goes to the fans.

Once you have found the wire going from the ac relay to the mag clutch you are in business. You need to splice into this wire and run a new wire over to the IACV. On the S14 SR20DET there are two "solenoids" on the IACV. One exists only for the ac idle bump, it is the one that runs horizontally with a purple connector. That new wire you have run needs to go into the Blue/Red wire on the IACV. This causes the idle to bump when you engage the AC.

Also as a side note, try connecting pin 9 on the ecu as above, but if you have issues with the AC not turning off once you have engaged it simply disconnect pin 9. Pin nine worked great on my stock ecu, but the ac would not turn off once it was on after I switched to a power FC. There seems to be no problems with pin 9 not connected.

need ac tooo..

Sorry to bump again--

OP: How did you get around the drier (the cylinder between the lines near the condenser) The OEM part has an electrical plug coming out of it, wheras the replacement part I got from "Four Seasons" does not have this hook up. I've double checked the part number and its for an S14 240SX. Just curious before I attempt to put this together.Thanks again!