[Joe M]

Not sure if this is the right spot, but here goes....brand new Classica with AT. I've only had it for a week but today I noticed, when I got in the car, the outside temperature gauge read 92 F. At first I thought it was because the car was in a hot garage, but even after driving it for about half an hour, the temp never went down. Outside temp was ~80F. So, anyone else having this problem or is it something I should take in for service?

I've got another question about Interior but I'll start another thread.

Thanks

 

[fabricio27]

Not sure if this is the right spot, but here goes....brand new Classica with AT. I've only had it for a week but today I noticed, when I got in the car, the outside temperature gauge read 92 F. At first I thought it was because the car was in a hot garage, but even after driving it for about half an hour, the temp never went down. Outside temp was ~80F. So, anyone else having this problem or is it something I should take in for service?

I've got another question about Interior but I'll start another thread.

Thanks

Is your outside temperature gauge change faster with the top up or down?

 

[kpoling]

Mine seemed pretty close to the actual temp - about 97 today and 99 yesterday - so it was reading a tad high and I've noticed its pretty slow to decrease but it does eventually get there.

 

[vandor]

I found that most cars these temp gauges are by the bumper and measure air that is close to the road, which is often warmer than the ambient air. However 12 degrees seems too much.
Definitely mention it during the service if the discrepancy persists.

 

[Chipshot]

Agree that sensor location makes a big difference in the initial reading. However, it should correct after 5-10 minutes. Depending where you're located, don't forget the urban heat island effect.

 

[zvezdah1]

mine reads 5+ degrees higher than actual outside temp.

 

[Joe M]

Agree that sensor location makes a big difference in the initial reading. However, it should correct after 5-10 minutes. Depending where you're located, don't forget the urban heat island effect.

I agree with it correcting itself after a few minutes. Not so with the Spider. Stays the same after half an hour or so driving. Not critical, but annoying. Not sure if it's worth an extra trip to service, just may wait till first oil change.

Thanks for the replies.

 

[wedgewa]

I'm not having this problem. I do get a high reading when starting after extended parking in hot direct sun but a little forward motion takes care of that.

 

[frankmar]

I just noticed my outside temperature is incorrect. It was about 0 C and after 25 drive it shows 14C. Definitely something wrong and unacceptable. My Murano, after 5 minutes of driving, it shows the correct temperature. I'll mention to the Service dept. for now it will go to hibernation, but next spring Fiat hope it finds a solution.

 

[Dabixi]

Mine I also slow. It can easily take half an hour or so before it has the correct reading after I leave the indoor parking at work.

 

[zvezdah1]

mine always reads 5-10 degrees too high.

 

[frankmar]

We should make a claim and result in a Recall for such problem. Unacceptable.

 

[kpoling]

We should make a claim and result in a Recall for such problem. Unacceptable.

I'm sure the outside temp is a Mazda design. These things are notoriously inaccurate - the ones in our BMWs aren't accurate either - usually a few degrees off one way or another. They also correct the temperature displayed over a period of time depending on time and distance driven, but the change is slow as you can read below from the Mazda forum:

From a Mazda Tech
Customers may comment that the ambient temperature indicated in the display (with and without Navigation) takes a long time to register the true ambient temperature.

Dealers should not replace parts to address this customer concern.

EXPLANATION: The AMB is programmed to start registering true ambient temperature after certain thresholds are met. These thresholds include engine temperature at the time of starting the vehicle, vehicle speed (over 32km/h) and time at speeds over 32km/h.

EXAMPLE

•If the vehicle has sat overnight and the Ignition key is turned ON, the actual ambient temperature will be displayed.

•If the vehicle has been warmed up, stopped (turned Off) and then restarted (IGN Off to On) the display will show the last temperature recorded.

EXAMPLE (with Ambient Temperature of 21 Degrees C):

•Vehicle is started, display shows 15.5 degrees C but ambient temperature is 21 degrees C.

•If the vehicle is driven at a constant speed over 32km/h.

•At the end of the first 90 seconds of constant speed the display will increase 0.5 degree C (60 > 60.5)

•After the first 90 seconds, the display will increase 1 degree for every 60 seconds (16.5 > 17.5, 18.5 >19.5 etc.) if the speed remains above 20 MPH, until actual ambient temperature is met.

•Display will not increase when the vehicle is in stop and go traffic or goes below 32km/h

 

[LongBeachJim]

My GM, Nissan, and BMW gave lousy readings. It's a technology which hasn't been perfected. The only time I ever look at the temperature is when the weather is extremely hot or cold. Even then, I know the car is only giving me a rough estimate. My body is the better gauge, lol.

 

[Redtoys]

we've been in the mid 30's in the morning, and gauge reading about 45. My drive in is under 15 minutes so it's either slow to catch up or off. Hasn't show a 30 anything temp yet.

 

[TomM]

*snip* good Mazda stuff

Sounds like they're concerned about distracting the driver with constantly changing temperature readings, so it's programmed to change slowly and only in situations that don't require full driver attention. Perhaps being in stop-and-go traffic could cause the temperature to spike and make drivers freak out.

That's laudable, I guess, but I wonder if it's based on an overly-cautious hunch or if they have actual data to support their design decision.

 

[ForzaFiata]

Call me crazy, but I'm of the mindset that instrumentation should be as accurate and immediate as possible. I never saw the point of "dummy" oil pressure gauges (looking at you, Ford), and temperature gauges which are just accepted as "inaccurate" are equally preposterous to me.

Exterior temperature sensors serve purposes greater than simply telling you whether or not you need a coat upon exit. Rapid temp swings need to be shown quickly if you're on summer tires (I've driven the Dragon enough times to tell you there's grip at 60° that doesn't exist at 40°)/

In my last performance car, the temp sensor also played a role in the ECU's fuel mapping; an artificially-high temperature would lean out the mix. We had an example of a guy whose car was "reading" 75° but it was actually 40°. The result was that his ECU had pulled fuel expecting IATs >70°F, and as a result, his AFR was in the 13s (should have been 12.0x under load based on actual ambient temp).

Not sure if the Magneti Marelli ECU works like the Bosch; maybe Greg can chime in.

 

[kpoling]

I'm pretty sure I've read that the sensor for air intake is separate from the dash display. The dash will eventually show the right temp if you are driving above the threshold speed for long enough. .5 degree adjustment for every 60 seconds - it will take a little time. So - the sensor itself no doubt is more or less accurate. The software is intentionally adjusting slower. Mazda technology, blame it on them.

 

[frankmar]

If a manufacturer is going to display a gadget(out side temp display) either you make it work right or don't even put it there. My 2011 Nissan Murano, displays a ACCURATE TEMP DISPLAY after 5 minutes driving. And it's parked indoor, even in winter where outside is -20c and indoor is +20c after driving 5 minutes temp is correct.

So I think Mazda or Fiat has done a poor job on this, it was better if they did not include such gadget.

 

[fabricio27]

Is your outside temperature gauge change faster with the top up or down?

After months of observing the outside temperature gauge to read correct, its change to its correct temperature at highway speeds after about 3 miles steady driving. Interesting!