Just so I don't get flamed, I've done a search and I've read Chuck's fix but I still have a question. My AC works fine on fan speeds 1 and 2, but not on 3 or 4. The AC light on the dash remains on, but on the Commander sensor display I can see the AC turn off when I flip the switch to 3 or 4. Is this the same problem that others were having or is this something different? I thought that Apexi had fixed all these problems in the latest release (I have the new version 5.something). My car is a 93 Base if that makes a difference. I'm pretty sure it worked with the stock ECU, but I never really used AC that much and just might not have noticed. TIA!

 

its luck of tho draw when it comes to the power fc and a/c in rx-7. in some people's car the a/c works fine. other, the a/c will not work at all. my car it only works on settings 1,2 and 4 when i put it on 3 the compressor stops spinning.

 

Consider yourself lucky. Mine only works on fans speed 1. I plan on using the a/c button to send a turn on signal directly to the compressor relay in the engine bay. I'm going to see how this works out. The only downside I see to this mod is that I won't have the auto turn off when I'm flooring it. Please enlighten me if there is anything else I'm not thinking about.

 

Mine doesn't work on fan speed 3. I thought that was cool since I could use it to manually turn the radiator fans on. Then one day I noticed the air coming out was cool, checked the sensor screen and noticed it was cycling the A/C several times a second. It seems like that could burn the thing up, so now I'm afraid to put it on 3 at all. Maybe I'm just paranoid....

 

Since installing a new engine wiring harness, my fan speeds 1, 2, and 4 AC work all the time now with 3 being flacky. I no longer run my AC bypass that was written up last year.

 

My A/C works perfectly on all settings. Guess I was one of the lucky ones. Cold as heck and blows like a ****

 

My A/C also blows cold on all settings. I replaced the '94 wiring harness when I put in the new engine to avoid this kind of stuff.

 

So I'm not the only one that thinks the A/C blows colder now (on the settings that still work)?

I lost #3 - 93 Touring with auto tranny swapped out for manual.

 

OK so does anyone know what was changed on the 94 harness, or what deteriorates on the OEM harness that causes this problem? Is there a way to fix this without bypassing ECU control of the AC and without swapping the entire harness?

 

This is a wild guess on my part, but maybe the problem resides in the switch control in the consol? Maybe there is poor electrical contact varying between 3 and/or 4 (and in some cases 1 and 2 too) from the manufacturer, and the Power FC is more sensitive to this??

 

Mine blows cold on one, flickers on 2, and just blows on 3 & 4. Luckily, I've never needed it to be much colder than what 1 can do.

 

A/C fine on 1 and 4, but just hot air in 2 &3.

No one ever found out how to fix this yet?

Any suggestions other than the possible harness switch?

 

Mine doesnt work at all as soon as the ac starts the cars idle jumps around almost stalling the car. Any ideas????

 

I have an R1 and the A/C works fine on all four settings but the **** sometimes does not work at all and usually when it is a burning hot day.

 

Mine now works on all settings. Here's what you need to do.

Your car has to be stolen and thrashed by some punk car thief. That's all that's been done to mine since my last post. and now all the settings work.

 

Just replaced my A/C fuse and it started working on all fan speeds. The air was pretty cool. Then suddenly the compressor stopped spinning and hot air came forth.

Any ideas? Could my refrigerant be low, causing compressor to shut off?

Steve

 

I don't think so, because it seems that it happens as soon as people put in the PFC.
Further to my above post, my A/C may or may not work on any setting now. 1 always works, 2 usually works, 3 & 4 rarely work. Any setting can stop working at any time, I've noticed that hitting a bump often causes it to stop working.

 

I installed a PFC about 6 months ago when it was colder and there was no need for AC. Now i have suffered from the lack of in Texas. The AC works for about 30 sec. on setting 1, and not at all on any other settings. I have a 93, any ideas.

 

Mine use to work on all the settings, but go off and on while on setting 3. Who the hell needs A/C anyway??? I just ripped the damn thing out. Wonder what is going to be like when I live in AZ???

 

Will replacing the 93 wiring harness with the 94 really fix the problem?

 

I just replaced my wiring harness on my '93 when I put in my new motor (my second rebuild). The old harness had 100K miles on it and was pretty baked. I suffered from the intermittant a/c issue, but not anymore. The a/c blows cold and strong on all settings.

My guess is the either Mazda did some upgrades to the harness and/or the old harnesses get baked by the heat under the hood and lose conductivity. While the engine harness was spendy (~$800 bucks for the part) it definitely solves the problem (at least for me).

Beast

 

Beast - Are you the guy with the upgraded twins? Did you replace with the 94 harness or just a new 93 one?

 

Yeah, I'm the guy. As far as which harness, I'm not sure. Checkpoint ordered it for me, and I doubt the part number is on my invoice. I think it's the later version because they told me it was slightly different, but I can't be sure. Please call them at 916-852-0306 and ask them what the part number was (tell them the upgraded twins guy sent you).

Sorry I don't know off the top of my head - you're the second person to ask me so I guess I'd better find out :-)

Beast

 

Mine does the exact same now, I thought at first setting 3 was just broken but then suprise it comes on cold sometimes now. Unfortunatley I need A/C...bad this time of year.

 

I have the same problem..I have no A/C but the stock ecu works it perfectly (I plugged it back in to check, cold a/c). My wiring harness is low mileage and is not brittle (soft). I took my power f/c out and put it in my friends car (94 touring) it worked his a/c perfect. I then took his power f/c out and plugged it in my car, still no a/c. It must be the wiring harness...They must have updated them sometime in 93 I would guess. You can jump the relay and the a/c will work all the time but for a hotday it's a quick fix. Just be sure to unplug the jumper or it will kill your battery if the car sits for a while without the engine running.