I hate this characteristic of my '02, I just hate it! I have driven lots of cars in the last 25 years and I too have never had to have A/C to get my windshield clear.

So here I am, at my first driving school in the S. It is a rainy weekend, I have the hardtop on. I like to drive "endurance" and stay out on the track for long periods; it helps my learning curve, so here I am, in the rain, on the track for more than an hour and 40 minutes, with the A/C on, that's just wrong! The driver's window was all the way down, so there was a lot of wind circulation, but there was a very hot body in the car and I had to have the defrost on, and I should not have been forced to run the A/C.

I can live with this characteristic on the streets, and now I know what I will be doing at the next track event in the rain, thanks rossmon1, I will find myself a nice little plastic box and keep it in my tool box for that fan clutch relay.

 

Jason B - great idea to ask modifry. Let us know what you find out!

TripleH - are you really in upstate NY and have never needed to use A/C to clear the window? Well, I guess I have never "needed" to use A/C, but in some conditions it makes a big difference. I can understand not wanting to use A/C at the track, though

Many, many years ago, I had a friend who bought an X-highway patrol car. In addition to the spotlight, it had a compressor defeat switch. It was a toggle switch under the dash which would be used to immediately shut off the compressor when necessary for a chase. I imagine it did something similar to rossmon1's mod.

 

Here's what I would recommend for a clean solution:

Hook a 12V relay up to the cruise control circuit.* When you put the cruise control master switch on, the relay closes and completes the circuit to the A/C compressor relay... thus allowing the A/C to run. When you don't want A/C to run, turn the cruise control master switch off, relay opens, compressor clutch won't engage.

No extra button required. Just a willingness to tap into a couple circuits with the Helm shop manual at your side.

*The (+) coil side would go to the light green wire coming off the back of the cruise control switch, the (-) coil ground to the car's ground. The normally open switch connections for the relay would be wired in series with the BLU/WHT wire coming off the back of the heater control panel. This wire goes to the pressure switch in the A/C system, which controls whether or not the entire A/C system runs. (When your A/C cycles off, it's because the pressure switch opens)

Let me know if anybody tries it

 

edit OH, you snuck in that post while I was thinking . . . but if anybody tries it - these wires may be easier to get to: end of edit

I don't have a 2002 wiring manual, but it's probably similar to 2000, in which case the "AC clutch logic" circuit is built into the HVAC control panel and can't be bypassed without actually re-working the circuit board - way too much trouble. And I have no doubt it's a legal issue found only in the "United Lawsuits of America".

Personally, I like Destiny2002's idea of using the Cruise control switch. I am a big fan of getting double-duty out of stock controls. My ROOF switch opens the passenger door and trunk, and my steering wheel cruise switches operate my shift indicator.

You can tap into the Cruise power at the Cruise Control Module up under the driver's dash (light green wire), but it may be easier to locate the light green wire on the brake switch. It's run through the brake switch so hitting the brakes cancels cruise. The light green wire has +12v when the Cruise Control is ON.

Connect it to one side of a relay coil and the other coil wire to ground. I'm guessing the compressor clutch pulls a few amps, so get a relay that will handle 5-10 amps. Then . . .

You can find the compressor wire at the ECM behind the driver's foot well cover. The rear-most connector on the ECM is the one you want, and the Blue/Red wire feeds the "Compressor On" signal from the HVAC controls to the ECM. It comes out of the ECM and goes to the compressor clutch on a Red wire, but there are 2 reds on connector A - I'd stick with the Blue/Red since there's only one of those.

You have to cut ( OMG!) the Blue/Red wire and put the relay contacts (normally open) in series with it.

Now when you want AC, you must have Cruise on too. If you turn Cruise OFF, the AC compressor cannot run.

.

 

Thanks modifry, I was checking my Helm manual after the initial post, sorry to do that to you

BTW, the pressure wire should be low current, almost any 12V relay should do. Radio shack sells a nice little one with a 30mA pull-in coil.

 

Bullshit link removed.

 

Thanks for the imput modifry and destiny. Don't know if i will use a relay however as I will probably just hook a mini toggle switch in series with both ends of the blue/red wire next to where i have my alarm system valet switch above the left side kick panel in front of the dead foot. Now that I know about the compressor enable circuit being in the cabin its an easy little hookup w/o relay or anything else.
Also I get annoyed by the little green cruise control light on the dash or the rear window defroster lite when driving at nite and wouldn't want it stuck on whenever i want the a/c enabled! I like to turn all the dash lites down to the bare minimum for nite driving to see the road better, close the stereo cover and eliminate any extra lites except some times when my consiousness has been expanded . and I like all the lites I can fire up!

 

Yes, I really live here, and at -4 degrees yesterday, I will admit I was asking myself why.
Yes, never needed A/C to clear a front window, winter or muggy summer, never been an issue.

What I would like to do is use the extra switch I have for the center console. I have an '02 and a hardtop, but when the dealer was doing the first '02 hardtop installation they did not realize the defrost was on the dash. By the time I straightened them out, I made sure they left me the switch and the bracket for no charge. So here I am with an extra switch, and nothing to use it for....

 

Good point!! ...... except I don't find anything annoying about the car, but that's just me. JMHO.

 

The defrost capabilities of every car I've ever owned has been helped by using the AC. I know its a pain that you can't turn it off, but it just doesn't seem that serious compared to most problems that sports cars have.