Cx-5 2017 ac

It’s an idiot gauge though. But yes on the service screen.

We've all heard of idiot lights. That's the blue cold temp light.

How do you define an "idiot gauge"?
 
So the gauge just stays pegged in the middle once the car is warmed up whilst the temp is actually fluctuating within its operating range. Even cars with the usual gauge actually do this. I believe they do it this way to reduce complaints to the dealer if the thing moves past the middle.

Not saying a digital gauge can’t be accurate just that they want to hide the temp fluctuations.

I believe it is programmed to move up when the engine is in fact getting too hot.

I should hook up the OBDII scanner and see how it relates to the temp. On my ST when I did this it would usually jump to its resting spot at like 185. However the temp would keep rising to usually 212 or so iirc and it would fluctuate a bit.
 
Most older cars I have driven don't have their gauge fluctuating. Should only move higher when there is an issue.

The CX-5's should be the same.
 
Yea that’s what I’m talking about and this definitely isn’t a new thing. I think the last car I had that had a gauge which fluctuated was a 2000 Saturn SL2.
 
Where does this info come from? In old cars, the fuel gauge had a ballast resistor to stop it reading the fuel surging in the tank but that’s done electronically now. The temp gauge has always reacted instantly to the temp sender and still does. If it appears “pinned” it’s because the thermostat and the fans are keeping it that way. Rest assured it will indicate the slightest hanged in temperature anywhere on the range.
 
All I am saying is it worked well in the past and should also on the CX-5.
 
Where does this info come from? In old cars, the fuel gauge had a ballast resistor to stop it reading the fuel surging in the tank but that’s done electronically now. The temp gauge has always reacted instantly to the temp sender and still does. If it appears “pinned” it’s because the thermostat and the fans are keeping it that way. Rest assured it will indicate the slightest hanged in temperature anywhere on the range.
[emoji106] I wasn't going to say it. Tired of debating. 🤣
 
So I ran a test. Plugged in my OBDII and went for a drive with the service screen and temp gauge selected.

Once OBDII was reading 190 the temp gauge on the dash had reached the middle which is labeled as 210.

The OBDII was at 190 for several miles of driving at 45 mph at about 95 ambient.

Once we encountered traffic it rose a bit to 195. Then once at a light it came up to 197 briefly then dropped back down to 195. Stayed there until we got to open road again and dropped to 192. Once we reached our destination it was at 194.

This entire time the dash gauge didn’t budge after reaching 210.

Empirical evidence based on observation of actual behavior.

I wouldn’t call that gauge accurate. I think it indicates engine is cold, warming up, at operational range, or overheating. Not real time accurate readout.
 
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Thanks for backing up your assertion with actual evidence, jthj.
Pretty good evidence, too.
 
It reads in accordance to the input signal. The input is from the temperature probe and is constantly variable between cold and boiling. There is no benefit in cost or function of it not doing.
 
My 93 RX7 analog dial was the same way.
I would argue that it was more critical to know temperature on a 13B-REW than on the CX-5.
I had to go aftermarket because by the time the needle got to H a light would come on but that is too late.

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But the AC on my 17 feels fine in 90+ degree Atlanta weather.
 
We take an annual trip in June to Arizona for my son's baseball tournament with his travel team. Last year, we took my 2017 GTI which has a digital temp readout...it always displays 194 degrees, regardless of the external temperature and driving conditions. We were coming back to California through Palm Springs and the external temperature was 123 degrees...GTI still displayed 194. Two weeks ago, we took the CX-5 on our annual adventure (loaded with 4 people, luggage compartment filled and my Thule roof box installed - same load as the GTI the previous year). The CX-5 temp needle did actually fluctuate from it's normal vertical position to a few ticks to the right. I was pleasantly surprised that the "needle" actually moved.
 
So I haven’t seen mine do this so this is a bit of theory with the CX-5. However, with other cars I’ve owned it will tick up once it gets above the range they determine for that middle position. Probably above 230 and I believe this is to indicate the engine is starting to get hot. Kind of a prewarning before you’re overheating. I think this is what that blurb in the manual is referring to warn you so you can take some action like turning off ac, slow down, pull over to let it cool down ect.

I will say in a previous car I experienced this with what remedied this happening was having the cooling system flushed and fresh coolant put in. Early 2000’s GM product in that case.
 
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