Thermometer Calibration?

[mycar]

My 2005 Vibe's External temperature display seems to be consistently 3 degrees too high. Anyone know if this can be calibrated? Thanks

[GrayFox]

that's pretty common for Vibes... I'm not sure about recalibration tho.

[RIT]

How do you know that it is off by 3 degrees. It is telling the temperature of the air above the road, and that is, most likely, warmer that the weather station's reported temperature, because it is probably in the sun, and heated up by cars, etc. Try sticking the sensor in a cup of ice water, and see what temp you get. I doubt if the digital thermometer is inaccurate - seems like Pontiaoyta ought to be able to get that correct !

[djb383]

Three degrees off compared to what????????

[GrayFox]

in this thread http://forums.genvibe.com/zerothread?id=23081people mention comparing to other temperature readings like the ones on bank signs and such....I'm guessing that's what he's using...

[kevera]

As long as it's under 5 degrees off,I really wouldn't worry about it too much.

[nygiantzz1]

It's a simple temp. sensor, no calibration. I think they are fairly accurate. I actually have 2 temp. displays, one is in my auto dimming rear view mirror. I mounted that sensor about 3" from the factory sensor and it consistently reads the same temp. as the factory sensor.

[Whelan]

Bank sign temps are about 15ft. off the ground. Next time you have a thermometer in your hand sit in the street, read it. Then get a 8-10' step ladder, now read it. There will be a difference.

[northvibe]

the thermometer is right in front of your radiator so I bet it gets some heat off of that. Some people have moved it off to the side or somewhere further away from the stock location so it doesnt get influenced by the engine heat....

[trayseelea'sboy]

I would just use a simple correction. If you think it is off 3 degrees then just subtract 3 degrees when you read it. If you really wanna check it, you can use an ice bath, but be sure to stir the bath when taking the reading. Also be sure the thermometer your using to compare it with is more accurate, (ie. reads to the tenth of a degree). Any temperature device that reads in °F to the whole number typically has a tolerance of ±2°F. If it reads in °C to the whole number than the tolerance is typically ±1°C.If you could find the circuit board for the temperature display there may be a potentiometer that you could adjust.PS. I am a metrologist / Calibration technician.

[mycar]

Thanks for the replies. It is handy to be accurate as it is a good indicator if roads are close to freezing. Yeah ,I know I can subtract 3 which is what I do, but accuracy is nice.Yes, I have been comparing the temp. display to bank signs. You guys are probably right about engine heat adding to the temp.

[Kari]

If your car is dark, this probably adds to the heat factor as well. Mine consistently reads high, but I don't think there is a way to calibrate it.

[ToolGuy]

My Vibe and Jeep both read high. I think it is a combination of road heat and engine heat of course strickly speaking when it is not a winter month for me. The Jeep once climbed crazy high once in traffic and I assume the wind was to blame for that. Once I drove it went back to where it should have been. I thought of but never did, making an aluminium heat schield to fit behind the sensor to lessen the engine heat.