Why you shouldn’t trust your car thermometer


GREENVILLE, N.C. (WNCT) – We’ve all done it a time or two or three on hot summer days. Jump in the car and oogle over the temperature shown on our dashboard display. But did you ever stop and wonder if it’s anywhere close to being right? Daniel Moore, a mechanic for 11 years, explains how it all works.

“There’s an ambient sensor, it’s on the outside of the vehicle,” said Daniel Moore, a mechanic at Greenville Nissan. “It’s actually a potentiometer so what it does is it reads the temperature over a long period of time and gives you an average.”

It’s not an actual thermometer and it’s not actually measuring the temperature second by second. But that’s not the only bad mark it.

When you’re trying to get a good temperature reading, it’s all about location, location, location of your sensor. On a Ford Escape for example, the sensor is actually back behind the bumper near the radiator and the engine. So the read out tends to be up a little higher.

“Depending on where it’s actually at on the vehicle, if it’s actually up in the front grill where you can get to it and see it directly, it usually reads a little cooler,” added Moore. “If it’s behind the bumper like a Ford per say, it’ll actually read a little warmer than normal.”

The temperature shown on the car dash tends to be between 5 and 10 degrees off the actual temperature, sometimes more in an extreme case. So the next time you take your car thermometer as gospel and feel the urge to post it to social media, remember this:

“It’s not to tell you 100% this is what the temperature is,” said Moore. “It’s just to give you a rough estimate so that when you get out of the vehicle, you know whether it’s going to be hot or cold.”

Copyright 2020 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Trending Stories