external temperature sensor does not reflect correct temp
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Joined: Jun 2006
Posts: 54
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From: Edmond Oklahoma
Outside Temp Still Wrong
I had the same trouble discussed in this thread (outside air temp incorrect) However, after I replaced the sensor in the air dam, the external temperature still reads the exact same temperature as the previous sensor did. What next?
Drifting
Joined: May 2000
Posts: 1,917
Likes: 3
From: Southern NH
Originally Posted by CPapin
I had the same trouble discussed in this thread (outside air temp incorrect) However, after I replaced the sensor in the air dam, the external temperature still reads the exact same temperature as the previous sensor did. What next?
What temp is it reporting?
- If it reports ~ 56*F, then the circuit is open, so check your connector for a broken wire or pin.
- If it reports a high temp (>120*F) then the circuit is approacing a short. The connector is probably corroded and is causing this. You can try to clean it or just cut it off and replace it.
Last edited by JC in XTC5; Aug 1, 2006 at 11:21 PM.
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Joined: Jun 2006
Posts: 54
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From: Edmond Oklahoma
I do not get a static temp. It will change depending on the outside temp, it is just materially incorrect. Currently on an 80 to 85 degree night it will read 50. During the 100+ day it will read 68. What am I looking for on the connector? I haven't found any exposed wires or corrosion. Thanks for the help, it is greatly appreciated.
Drifting
Joined: May 2000
Posts: 1,917
Likes: 3
From: Southern NH
Originally Posted by CPapin
I do not get a static temp. It will change depending on the outside temp, it is just materially incorrect. Currently on an 80 to 85 degree night it will read 50. During the 100+ day it will read 68. What am I looking for on the connector? I haven't found any exposed wires or corrosion. Thanks for the help, it is greatly appreciated.
Other than that, if the temp is inaccurate then the circuit still as some unwanted impedance somewhere that's causing the overall impedance to be off. For the corrosion, check the internal wiring harness connector pins. If you spray some WD-40 into it that should dissolve any corrosion. Otherwise I don't know where else the problem could be.
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Joined: Jun 2006
Posts: 54
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From: Edmond Oklahoma
I do have the correct part, assuming the part that was on the car is the correct one. I'm about 99% sure we're good there. I'll try the advice when I get home. Hopefully, there isn't a hidden short in the wire somewhere. It sounds as if I've gone as far as I can go w/o professional help!
Drifting
Joined: May 2000
Posts: 1,917
Likes: 3
From: Southern NH
FYI - I double checked the wiring diagrams and the external temp sensor connects directly to the HVAC controller, so there are no other circuits that could affect the impedance.
Try this if you still have problems:
If you're still having a problem, then the only other possibility is the HVAC unit has a problem internally where the sensor impedance is used in conjunction with it's reference circuit. The reference circuit consists of a 5V voltage and a reference resistor. I can't see how it could be this though.
Also remember that the display will not update if the car was started less than 3 hours ago. You need to drive it above 20 MPH of 90 seconds or above 45 MPH for 60 seconds.
Try this if you still have problems:
- Disconnect the sensor. You should get DTC B0333 Outside Air Temp Sensor Open, and the temp display should default to 56*F. This would tell you that there are no shorts in the wiring harness/connector.
- Short the sensor connector - this won't blow anything. You should get DTC B0332 Outside Air Temp Sensor Short to Ground, and the temp display should default to 56*F. This will confirm that there are no random impedances in the circuit.
- Measure the impedance of the sensor itself. At 68*F, it should measure 12,493 ohms. At 86*F/8,056 ohms, 104*F/5327 ohms. That should be enough to verify it's within its expected range.
If you're still having a problem, then the only other possibility is the HVAC unit has a problem internally where the sensor impedance is used in conjunction with it's reference circuit. The reference circuit consists of a 5V voltage and a reference resistor. I can't see how it could be this though.
Also remember that the display will not update if the car was started less than 3 hours ago. You need to drive it above 20 MPH of 90 seconds or above 45 MPH for 60 seconds.
Last edited by JC in XTC5; Aug 1, 2006 at 11:24 PM.
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Advanced
Joined: Jun 2006
Posts: 54
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From: Edmond Oklahoma
John, I'll give it another go with the info you left on this thread recently. I may not have driven the car fast enough the other day for it to register. I simply rode around in the driveway back and forth and let the car sit and run for a few minutes.
I assume a small paperclip touching both metal prongs will short the connector?
Thanks for all the info and lets hope this works!
I assume a small paperclip touching both metal prongs will short the connector?
Thanks for all the info and lets hope this works!
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Joined: Aug 2010
Posts: 60
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From: Avon Park FL
still not working
i am having same problem. a few days ago i noticed that the outside air temp gauge was 69 even though it was over 90 and the a/c quit blowing out cold air. I followed the advice on here and disconnected the sensor but the a/c still would not blow out cold air. Replaced the sensor and now the outside air temp is correct, however, the a/c still will not blow out cold air. Does anyone know what else I could try?
Race Director
Joined: May 2000
Posts: 14,542
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i am having same problem. a few days ago i noticed that the outside air temp gauge was 69 even though it was over 90 and the a/c quit blowing out cold air. I followed the advice on here and disconnected the sensor but the a/c still would not blow out cold air. Replaced the sensor and now the outside air temp is correct, however, the a/c still will not blow out cold air. Does anyone know what else I could try?
Advanced
Joined: Aug 2010
Posts: 60
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From: Avon Park FL
Advanced
Joined: Jun 2006
Posts: 54
Likes: 0
From: Edmond Oklahoma
You could try to pull your battery cable and see if it may reset the system. Also, you may have a problem with the internal sensor (assuming you're using the auto a/c feature). Also, look for some damage to the wires near the outside sensor. Some people suggested that could cause an issue too.
It seems like i've read something on the dual zone a/c unit acting like yours, but it's been a while. You might look in the forum and see if there was a fix for that.
It seems like i've read something on the dual zone a/c unit acting like yours, but it's been a while. You might look in the forum and see if there was a fix for that.
Advanced
Joined: Aug 2010
Posts: 60
Likes: 0
From: Avon Park FL
You could try to pull your battery cable and see if it may reset the system. Also, you may have a problem with the internal sensor (assuming you're using the auto a/c feature). Also, look for some damage to the wires near the outside sensor. Some people suggested that could cause an issue too.
It seems like i've read something on the dual zone a/c unit acting like yours, but it's been a while. You might look in the forum and see if there was a fix for that.
It seems like i've read something on the dual zone a/c unit acting like yours, but it's been a while. You might look in the forum and see if there was a fix for that.