Gearhead Jim

PROBLEM SOLVED. SEE POST #38.

Recently we took a weeklong trip to Vermont in our 2017 Z51.

One morning after parking outside overnight, the reported outside temperature was 36' and some of the cars had frost on them. When I started our car and checked the Tire Temperature display before driving, it said "Warm".
WTF?

A few days later the outside temp got into the high 70's and we drove for a couple of hours. The tire temperature still said "Warm", which is more believable.

Can someone explain the temperature readouts?

themonk

My guess is that it wasn't an instant readout, just a "left over" from right before you turned it off. You cited that on a 70 day after driving a couple hours it said warm, which is normal. I suspect that on a cold day that if you drove a little bit (not a couple of hours), just enough to "reset" the reading you will get a "cold" readout, but hey I'm not a GM engineer, I just like to think I am.

Gearhead Jim

In this particular case, I kept the temperature display visible for a while as we drove, then went to normal display but kept checking Tire Temp for a while longer. It never changed to Cold or Hot at any time during our 2,600 mile trip.

I don't think GM is going to hire either of us...

Zymurgy

Temperature readouts:

ExRedRacer

Last winter, I drove my '16 Z51 to a friend's house in the afternoon and didn't leave until later that night. It was in the low to middle 30's outside and upon starting the car, the tire temps indicator showed Cold and instead of the normal orange color of the tires, they showed a light blue. When starting my car inside my garage with outside temps in the 30's and above, it always indicates Warm. But that night after parking outside for several hours, it was definitely showing Cold.

Something seems to be not working correctly with your indicator.

pickleseimer

Here is a duplicate of a post I made about 2 years ago regarding tire temp displays, with credit to Edmunds.Com
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From Edmunds.com:

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"Integrated Tire Temperature/Chassis Controls

Chevy uses the tire temperature data available through the C7's tire pressure sensors to more carefully control its ABS and electronic differential. Because the pressure sensors don't measure tire temperature directly (they actually measure the temperature of the TPMS sensor's microprocessor), it's not a perfect science, but it is one that data modeling can largely overcome. And it's one more piece of information that can be utilized to enhance the driving experience.

Tire temps are split into three categories: cold (below 45 degrees), warm (45-115 degrees) and hot (above 115 degrees). In "cold" mode ABS intervenes sooner and more progressively, while the differential is more aggressive to limit inside wheelspin. As temps increase, ABS control intervenes later and becomes more lenient, while differential locking ramps up more slowly."

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So, as per the above, it may be inconsequerntial information to display to the driver, however the data is used by the systems on the car. Frankly I would have preferred to see the actual computed temperatures displayed rather than the classifications of cold, warm, hot etc.

Turns out these numeric temps can be viewed if you have a PDR and download the Cosworth Toolbox to your PC. Run your PDR video into the Cosworth software and numerical tire temps can be seen in the toolbox display screens.
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Cliff8928

Nice. I was wondering how the readout corresponded to actual temperatures. All I can say is that "Warm" is significantly less grip than "Hot" with the Cup2s.

DWRAT

There's a tire temp reading???
Is this in a base C7 also?

Cliff8928

The temp readout is in the "perf" displays where the additional gauges and G meter are.

Foosh

Yeah, if your car is garage kept, you may never see "cold" or "frozen." I haven't even though my car is daily driven year-round. It's in a garage both at home and at work.

Nonetheless, "warm" on the display is not necessarily warm if you're talking about below 50ºF, and the PSS tires are very slippery at those temps.

JerryU

Thanks. In 3 1/2 years my 2014 read Cold just few times! I park in an attached garage so it only gets below 46 degrees occasionally. After a short drive, even when it's 40 outside, it changes to Warm.

I assume they are using an increase in tire pressure when driving to estimate tire temp. They are not measuring the temperature directly.

In Eastern SC have had it read Hot with spirited driving when it's 95 outside.

kitesurfer

mine reads the actual temp of all 4 tires. Is it broken?

edit; do I get a stupid award? it reads pressure!!!!!!!!!!!!!!!!!!!!!!!!!!!

Foosh

I've never heard of that before. What year is your car?

My '14 just shows color-coded graphic display with the labels described in post #4 above. Show us a picture of the temp read-outs on your car.

Gearhead Jim

With the conditions described in my original post, I can't see how my tires could have been above 46'.
A Z06 in our group also said his tires indicated "Warm" immediately after starting, on another day when the temperature was below 40' after parking outside overnight.

Somethin' strange about the system...

TEXHAWK0

The car display does just show the color coding for tire temperatures but the sensors do transmit actual temperatures. If the software allowed it, the temp. could be displayed on the dash.
Here is my hand tire pressure sensor reading tool display.





Here is what FROZEN looks like..

Zymurgy

There is actually a temperature sensor on the TPM microprocessor. It measures the temperature of the chip and then "alogrithms" are applied to estimate the tire temperature. From pickleseimer's post above:

Foosh

Zymurgy/Tex/Jerry

Yes, I was just wondering how the poster quoted above was seeing this in his car.

DanZR1

I just got back from a 1700 mile trip through the Rockies. One morning leaving Dillon it was 26 degrees. At start up, tires read Warm. Drove a bit and it never changed. I have seen Hot before, so it's reading something. I too found it odd that they never got Cold.

So it's not just you, Jim...

ClydeFrog

That tire temp display is useless & should never be used to figure your tire grip status. It’s basically telling you if its warm or cold outside. I always leave my tire pressure display up & don’t get on it until I see around a 3psi increase all the way around.

Avanti

Another virtually worthless datum I won't need to worry about.