Thermometer not accurate

Pinuz

New member
Hi guys,
I tested in the last week the 4runner thermometer and I can assure that is accurate only on positive degrees.
I'm in Canada so we use Celsius Degrees.

FIrst I don't like the fact that takes 20 minutes to show the themperature.

Below zero is about 2 degrees more than the real outside themperature.

Now for example my two external thermometers sign -2.7 amd -2.6 and the 4runner is 0 (this is in my back lane near the garage).

Other days when the outside was around -5 the 4runner in the same position sign -3.

The weard thing is that on positive degrees is pretty accurate, sometime just 1 degrees difference.

Anyone tryed to mesur it?

thanks and have a nice day.
 
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It's as accurate as any car thermometer can be.....heat from the engine and it's various cooling systems will invariably effect any thermometer mounted on a vehicle.

You'll notice it more the colder it gets, as there will be a larger discrepency between the actual air tempertare, and that coming off of the vehicle.
 
BMW and Mini = same company.

Temperature gauges are there to provide a temperature as accurate as it can. Due to certain areas in which the readings are taken, it might be "not as accurate". Car temperature can affect readings. I've had my temperature gauge tell me its -29celcius but with windchill its alot colder than that and that its different then what "theweathernetwork.com" says.

Another thing... its like the weather forcasted by the tv, radio, etc. Its not accurate but it will give a rough estimate of the overall weather. Weather in the North-West is different then the weather in the South-West. It all depends.
 
Thats why I used my two thermometers (one is lacrosse and another one is old stype) and the car in my backlane (no wind), just for compare what I suspected on the road and when I compared side by side the two car's thermometer, 4runner is 2 degrees difference even in the highway.
 
Pinuz said:
My Brother in law Bmw 545i is accurate and even a little Mini Cooper is accurate.
And my 325i wasn't, in fact that car fluctuated a lot with engine heat....differerent cars have them in different spots.

Basically, it's accurate for comparison, but not for exact numbers. If you're driving an it goes from 10-15, the temperature went up 5 degrees, but it's not necessarily 15 degrees exactly. Thermometers in vehicles are obviously calibrated fairly slow, as temperature can change drastically in very small distances.....
 
I have a black Volvo and in the summer, when there is no wind to move outside air past the sensor, I sometimes see readings over 120 degrees when I first get in the car after it has not been driven for a few hours (aproximate outside temperature in 90's). The first 10 or 15 minutes of driving the temperature gradually comes down close to what the actual outside temperature is. Also, again if there is no wind, and I'm in a traffic jam, the engine heat will gradually cause the car outside temperature reading to increase, sometimes up to over a 100 when it's really only around 70 outside. Most cars will show there most accurate temperature reading when driven on the highway with plenty of air rushing past the temperature sensor, where ever it is located on the car.
 
When its reading below on the thermometer, I don't care how accurate it is because my cajones are still freezing... :arrow:
 
I'd say a couple degrees off is accurate. You have to remember where the thermometer is located, behind the front grille. The engine bay emits some heat which will undoubtedly be taken account for by the thermometer. I don't really need an accurate reading, as long as it's relatively close, I'm happy.
 
Northof49 said:

You'll notice it more the colder it gets, as there will be a larger discrepency between the actual air tempertare, and that coming off of the vehicle.

Actually, I've noticed just the opposite.

I drive past one of those digital clocks/thermometers that you often see at banks every day and I'm in the habit of checking my outside temp display with it. In the winter, it always seems to be within 2 degrees, but in the summer it can be as much as 5-7 degrees different. I always thought that the heat reflecting off the road on a hot summer day caused this to happen.

I also have a digital thermometer in my garage (which is not heated, but never drops below 45 degrees because it is built into my house) and I glance at it every day when I back my 4Runner out of the garage. My outside temp display is always one or two degrees under the garage thermometer, regardless of the outside temperature. I never idle my 4Runner in the garage, however, so the engine heat is not a factor.
 
sharp4runr said:
When its reading below on the thermometer, I don't care how accurate it is because my cajones are still freezing... :arrow:

You've got the same one I have. The colder it gets, the smaller they . . . . er, harder to read. :D:D j/k

Mine is always with in two degrees to the warm side. That's plenty accurate for me. No vehicle thermomerter will be as correct sitting still as it will be when moving. It will also read differently on black asphalt versus concrete because of radiant heat.

Coming home a few minutes ago mine read 9 degrees when I started it up and 9 one mile later. Crap, 11 or 9 or 7 is still COLD.

Anythig below 20 and calm is cold and below 20 with wind is damn cold. Anything else is just numbers.

Same is true for 95 being hot and above 95 . . . . damn hot.
 
Probably depends where the sensor is, if it's in the open and sits in the sun all day then it's going to read hotter. Just like if it's 90 out and your car sits in the sun, the surface is much hotter than 90 right? As for the wind, thermometers do not measure wind chill because they don't feel wind chill, same as your car. When it is 20F out at my house with 20mph wind its still 20 to my truck even though to me it feels like -10. You'd need an extra sensor to measure wind speed and then calculate wind chill accordingly. Wind chill was developed by the US military using gallon jugs of water and timing how long it took to freeze at varying temps and wind speeds back in the 50s, their data was inaccurate which is why all the wind chills were changes several years ago, it is now seen as warmer than before as skin does not react the same as water. Just like over 50 mph it no longer matters for wind chill, 50mph feels the same as 70 mph, just pushes you around more.
 
Perhaps I am lucky for I have faith in the thermometer reading. Last week, we had arctic air, with day temperatures of as low as -30 C. The outside temperature gauge read accurately. I have a temperature gauge in my garage - it read -3 C, as did the truck. My girlfriend has a GM truck with outside temperature, and on a recent trip, we were at most 1 degree C different. If the vehicle has been running, it takes a few minutes for the temperature reading to stabilize.
 
I really don't mind if the thermometer is off by 5 degrees when it is cold. What I do mind is that the thermometer only goes to -22F. I need it to go to at least-60F!!!
 
carina71 said:
I really don't mind if the thermometer is off by 5 degrees when it is cold. What I do mind is that the thermometer only goes to -22F. I need it to go to at least-60F!!!

LOL, it probably froze first. :D
 
carina71 said:
I really don't mind if the thermometer is off by 5 degrees when it is cold. What I do mind is that the thermometer only goes to -22F. I need it to go to at least-60F!!!
Is there really a -60? I thought that was below absolute zero!! :D
 
jharris2 said:
Is there really a -60? I thought that was below absolute zero!! :D

No, it's not absolute zero, but here is the layman's scale (from personal experience):

30F chilly

0F cold

-35F really cold

-65F GD COLD!:eek2:

-88F the coldest recorded temperature in North America

And I'm not sure, but any colder than that I think hell might freeze over!

After that, by a long ways, there is absolute zero. Now, I'm no Einstein, but I think one could argue that at absolute zero, even time would stop.
 
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LOL, after the polar (below 20 degree) air you've been sending all of us for the last few weeks, it hit 27 the other day with full sun. I was outside wearing jeans T-shirt and flip flops with the water hose washing the 4Runner. It felt great. Neighbors thought I was nuts. Flip flops? I didn't want to get my shoes wet. :D
 
carina71 said:

30F chilly

0F cold

-35F really cold

-65F GD COLD!:eek2:

-88F the coldest recorded temperature in North America


Let me add one to your list:D :D

-459F is equal to absolute zero (on the Kelvin scale) and is just a little bit under that record temperature for North America!! At that temperature, everything almost stops!!
 

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