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Discussion Starter · #1 ·
I've been having a weird AC issue for the last year or so that's been too intermittent to pin down. I've looked through other threads and gotten some hints, but haven't found this same problem. I was hoping I could list the symptoms and see if anyone can help.

AC blows super cold when it's working, but the compressor cuts off at random times and starts blowing hot air. The one common variable I've figured out for sure is that it happens often when its been raining. Here are some other observations:


  • The way I know it cut off (besides the hot air) is the recirculation light goes out. This sometimes happens when I start it up and other times while I'm driving.
  • Cuts out more often when I have the fan very low. I'm not sure why fan speed would matter, but if I keep it blowing high it seems to run longer.
  • If it doesn't kick on when I first start the car up, I can sometimes restart the car and it will work. But when it shuts off during rain, I can turn the car on and off a hundred times and it won't work again until I've parked for a few hours.
  • The outside temp reading is sometimes ---- and other times just random numbers. I haven't found a pattern yet, but I suspect the temp sensor. I believe it is by the front bumper, but I don't know what it looks like or how that ties in to the AC.
  • Seems obvious that this is an electronic issue... maybe a short that gets worse when it's wet. I also suspect the serp belt though..., maybe it slips when wet. IDK. I'm handy but no mechanic so I'm hesitant about digging into anything blindly.
Any ideas would be greatly appreciated.

Thanks,
Jared
 

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Replace the temp sensor. It sits in this hole.



Might want to check the harness for it too. Over on driver's side. Just follow the green and blue wires coming out of it. Looks like this:

 
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Discussion Starter · #3 ·
Thanks, Diggs. Yeah there's nothing in that hole so that's probably a step in the right direction.

Does the wiring harness run through the drivers side fog light area? There's a bunch of loose wires under there, looks like someone cut the harness and left them hanging (bought this used a couple years ago). I wrapped the wires up and dried everything out yesterday. The dash temp reading is now a solid ---- and the AC has been cold so far today. I guess that means I isolated the sensor signal so it can't short out and give faulty readings.

I'm confused as to why this affects the compressor though, since this is the outside temp sensor. I'm guessing the outside and inside sensors are polled periodically and if it appears to be colder outside the system will shut the compressor down and pull air from outside rather than recirculating. Does that sound about right? If that's the case, is there any reason I need to replace the outside sensor (besides just wanting to know what the temp is).

Thanks again!
 

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Yes...the wiring hardness is in the area of the driver's side fog light. People have issues with that area all of the time including myself. It gets affected by curbs, snow, etc. Once that happens water gets up there and your temp sensor and/or fogs will have issues.

A dash temp of --- is not good. Your AC will work intermittently because it needs to know what the outside temperature is. You should get a temp sensor to start with and see if that fixes the problem.

https://www.eeuroparts.com/Parts/33011/Outside-Air-Temperature-Sensor-9152245/
 
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