# Outside temperature sensor



## Uplink (Jul 8, 2016)

I remember seeing some info in the past, but can't seem to find it... But I am butting heads with the Chevy collision center that after my car was repaired, my ac doesn't work when it rains... I've read that this is a cause of the outside temp sensor getting wet. Of course they've never seen this before and need to look into it. I had my front bumper replaced along with the hood. Where exactly is this sensor located and could I have a picture of what it should look like?


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## obermd (Mar 3, 2012)

The sensor is located in the left front fog lamp bezel. It sounds to me like the connection isn't secure and is getting wet and shorting out, which makes the car think it's a lot colder than it really is. I'm assuming it worked prior to the collision, in which case the repair hasn't been completed.


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## Tomko (Jun 1, 2013)

Do you have fog lights?


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## NickD (Dec 10, 2011)

Fog lamp bezels or the fake ones are the same for location of the ambient sensor, on the left hand side.

Is a thermistor with a negative temperature coefficient, so the colder it gets, the greater the resistance it will have. But the key indicator for proper operation is just looking at your radio outside temperature gauge, should be about the same as what the weatherman says. If that is way off, sensor or its connectivity is your problem.

Also a harness going to your AC compressor, for both the clutch pull in electromagnet and the displacement control leads, is in that neighbor and can also be your problem.


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## Uplink (Jul 8, 2016)

thanks guys, I don't have fog lights but I do know where you are talking about. The outside temp gauge is non existent unless it rains, then it's -40.


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## NickD (Dec 10, 2011)

Use to be a high pressure switch in the high side line with real contacts that only remained closed in the 40 to about 390 psi range. Outside of the range, the circuit was broken for the AC clutch solenoid. This was replaced with a 17 cent thermistor as is direct relation between pressure and temperature, but you can't tell this from the sticker price that goes up every year.

You sure have an open circuit, but question rain giving some conductivity, should be a small shield under the front bumper to shield that thermistor contacts from water, unless this is missing, who looks under the car. So is this sensor missing or just not plugged in?

This is what it looks like:










Like anything, it snaps into a holder at the rear of your bezel and a lot easier to snap in than to unsnap, two long plastic prongs hold it in, if they broke those off, probably said screw it, doesn't need this thing anyway.


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## obermd (Mar 3, 2012)

Uplink said:


> thanks guys, I don't have fog lights but I do know where you are talking about. The outside temp gauge is non existent unless it rains, then it's -40.


-40 is an open circuit and is the default reading. Your temperature sensor wasn't reconnected properly when the bumper was put back on.


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## NickD (Dec 10, 2011)

When Mount St. Helens blew her cork in 1980 our winter temperatures dropped to -45*F due to all that junk she put in the upper atmosphere. -40*F is not enough range. 

Obama was only a 19 year kid back then, guess he doesn't remember this back then.


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## Uplink (Jul 8, 2016)

Amazing response, just what I need to show to the collision center who has never seen this before. Thank you!!


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## Uplink (Jul 8, 2016)

I also noticed this exposed inside. It's tucked down by the hood release, should there be a cap on this to bridge those connections or what does this do? Funny enough, 2 of my tire air valves are missing caps after repairs as well...


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## NickD (Dec 10, 2011)

If I understand this, you are looking at the diagnostic connector where you connect a scanner into, looks normal.

Less then a thousand miles on our brand new Cruze, power steering died, dealer replaced it under warranty, check their work when done. Screws and push pin rivets for the undercover were missing, two were broken off, this was off to a bad start. But did give me all the parts I needed to correct their very poor work.

Bit later they want to butcher that under cover, said no way.


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## Uplink (Jul 8, 2016)

NickD said:


> If I understand this, you are looking at the diagnostic connector where you connect a scanner into, looks normal.
> 
> Less then a thousand miles on our brand new Cruze, power steering died, dealer replaced it under warranty, check their work when done. Screws and push pin rivets for the undercover were missing, two were broken off, this was off to a bad start. But did give me all the parts I needed to correct their very poor work.
> 
> Bit later they want to butcher that under cover, said no way.


Do you know if there's supposed to be any cover over it? I never recall seeing this exposed in my almost 2 years having the car... But I've never really put my head down there to notice before.


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## obermd (Mar 3, 2012)

Uplink said:


> I also noticed this exposed inside. It's tucked down by the hood release, should there be a cap on this to bridge those connections or what does this do? Funny enough, 2 of my tire air valves are missing caps after repairs as well...


That's the ODBII diagnostic port and it doesn't have a cover, but probably should.


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## NickD (Dec 10, 2011)

Was nice, had my power switch iCar ELM 327 bluetooth plugged in there, so when the CEL came on, hit the switch and knew exactly what the code was.

Not so nice on this Elantra thing, hidden behind the fuse cover, too tight to plug in the iCar, so when the CEL comes on, and it will, they all do this. Have to remove the fuse cover, try to remember where I buried my iCar, plug it in, then learn why that stupid Check Engine Light is on.

What, the oil dipstick if not fully pushed in, oil or gas cap not tight, someone swiped my gas cap, or is the engine going to be toast. Really don't need a code that tells me the power steering went to pot or the ABS light is on because I have a flat tire. And sure don't get a code when the brake pedal goes to the floor, but don't tell my dealer this, you ain't got a problem, ain't getting a code.

Ha, recall the good old days when people had brains.


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