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Discussion Starter #1
My outdoor temperature display consistently shows about 5 degrees higher than the actual outdoor air temp. My previous cars have been very accurate. Even with the car sitting n shade and even after driving it for awhile, the temperature is still over stated. Has anyone else noticed this and/or is there a way to make an adjustment? Thx!
 

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the question is what are you comparing it with? how do you know the car is wrong and the other device is incorrect? The dealer might be able to calibrate it down 5 if it really bothers you that bad.
 

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I've never owned a car where the temp display wasn't 3-5 degrees off. I've always just subtracted a few degrees ha.
 

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I've never owned a car where the temp display wasn't 3-5 degrees off. I've always just subtracted a few degrees ha.
Exactly. The proximity of the temperature sensor to hot surfaces (roads) and/or direct/indirect sunlight can easily make it read high. Just like bank thermometers that you see are worthless on sunny days.
 

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All of those factors would affect other cars too, but I have to agree that this car seems far less accurate then many of the others I have owned as well. Others were maybe one to two degrees off sometimes, this one seems to be always 5 degrees high. Oh well, it may not be accurate, but at least it seems to be precise.

Sent from AutoGuide.com Free App
 

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Mine is about 5° high as well, I just figured it was due to the fact that the car is black. It's a little annoying but nothing that can't be solved with some simple math.
 

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You guys talking in degree F? Yeah, it's probably about 5 degrees F off, or 3 degree C. Not sure where the sensor is, but I suspect engine heat has a factor.
 

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It's definitely about 5 degrees too high. I was watching it today - knowing the high was 87 out - and it showed 92 the majority of my commute home (28 miles on the highway).
 

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Discussion Starter #12
Well, my point of reference is weather.com and/or my phone app. My Subaru always displayed the exact same temperature as my phone or if I passed a bank thermometer, my car always displayed the same temperature as that. However, with this car, even when the car is cool (1st thing in morning) and not sitting in the sun, the immediate temperature reading is high. Not a big deal, I was just wondering if anyone knows a way to calibrate this (other than going to a dealer)
 

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Discussion Starter #13
It's definitely about 5 degrees too high. I was watching it today - knowing the high was 87 out - and it showed 92 the majority of my commute home (28 miles on the highway).
Yes, that's what I'm noticing as well, even after driving quite a distance.
 

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If those numbers some billboards along the road are posting are accurate, then the MZ3's number is off. I would argue it is because Mazda cut corner on the temp sensor housing, since the temp has usually a big jump (down or up) after driving a while.
 

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No car (or roadside billboard or bank sign) is going to give you a truly accurate temperature reading. I was a weather observer in the Navy long ago and I remember that there were a whole set of specifications about where and how an official temperature reading could be taken. I found this on the National Weather Service's website:

"Temperature sensor siting: The sensor should be mounted 5 feet +/- 1 foot above the ground. The ground over which the shelter [radiation] is located should be typical of the surrounding area. A level, open clearing is desirable so the thermometers are freely ventilated by air flow. Do not install the sensor on a steep slope or in a sheltered hollow unless it is typical of the area or unless data from that type of site are desired. When possible, the shelter should be no closer than four times the height of any obstruction (tree, fence, building, etc.). The sensor should be at least 100 feet from any paved or concrete surface".

Your car has a hot engine and is driving on hot pavement surrounded by other vehicles spitting out hot exhaust. I think it's a safe bet that your car is almost always going to report about 3-5 degrees (F) higher than any "official" reading.
 

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No car (or roadside billboard or bank sign) is going to give you a truly accurate temperature reading. I was a weather observer in the Navy long ago and I remember that there were a whole set of specifications about where and how an official temperature reading could be taken. I found this on the National Weather Service's website:

"Temperature sensor siting: The sensor should be mounted 5 feet +/- 1 foot above the ground. The ground over which the shelter [radiation] is located should be typical of the surrounding area. A level, open clearing is desirable so the thermometers are freely ventilated by air flow. Do not install the sensor on a steep slope or in a sheltered hollow unless it is typical of the area or unless data from that type of site are desired. When possible, the shelter should be no closer than four times the height of any obstruction (tree, fence, building, etc.). The sensor should be at least 100 feet from any paved or concrete surface".

Your car has a hot engine and is driving on hot pavement surrounded by other vehicles spitting out hot exhaust. I think it's a safe bet that your car is almost always going to report about 3-5 degrees (F) higher than any "official" reading.
Spot on! ;-)
There's no guarantee about the temp sensor accuracy/sensitivity either for car, bank, roadside or backyard weather station/internet thermometers.

WeatherDan (meteorologist!)
 

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My Mazda says one thing, my phones says another, and the bank still another. They're all within a few degrees of one another, + or -, and it doesn't change my life. Maybe I'm missing something here, but why would a few degrees, + or -, really matter. Obviously, sensors placed in different locations, within just a few hundred feet of one another, are going to have different readings. If you were able to adjust the reading, in the car, what would you adjust it to? What would you consider "accurate"? It would still, at times, show a different reading than, say, your phone or the bank reading. And, at other times, be spot on.
 
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