What wheels do you have? 32 might be on the low side. I don’t recall offhand what mine are, but I’m pretty sure it’s higher than that. The cold will definitely cause the pressure to drop.
As for just the one wheel, I’d say it’s probably a rounding thing. It’s probably a few tenths lower, barely tripping the alert.
@Clove
I don’t know, but the tires and the pressure have been the same the entire time I’ve had it.
Kameron said:
@Clove
I don’t know, but the tires and the pressure have been the same the entire time I’ve had it.
Tire pressure always changes with temperature, and tires do tend to slowly lose pressure over time. It’s pretty normal in places with winter to have to top up tires in the winter.
Kameron said:
@Clove
I don’t know, but the tires and the pressure have been the same the entire time I’ve had it.
How long have you had it? Tires lose pressure over time, and as the temps get lower, it makes the air in the tires denser, which lowers the pressure.
@GreenBrown
Density is mass per unit volume (m/V).
Let’s use
P1/T1 = P2/T2
from the combined gas law (of Charles, Boyle, and Gay-Lussac).
Decreasing the temperature (from T1 to a lower T2) means that the new pressure (P2) must also decrease.
@Harper
I’m a little lost at the point of your reply.
GreenBrown said:
@Harper
I’m a little lost at the point of your reply.
Did the mass of air change? Did the volume of the tire change? Did the density change?
Did the pressure change due to a change in density?
If you cannot answer these questions, it’s no wonder you’re lost.
As others have said, it comes because you went below a certain threshold. If you’re confused why that specific tire is yellow and the others aren’t, it’s because it won’t reset until it’s back to the set pressure level (printed on the inside of the driver door). So basically, that tire went too low and has come back up slightly to match the others but not high enough to reset the warning.
Mine came on this weekend due to the cold dropping tire pressure. You can either drive it around and see if the pressure recovers once the tires warm up, or just add some air. Mine didn’t self-resolve but cleared as soon as I added air.
Mine was the rear left too, but it seemed to be a little lower than the rest.
I remember my front wheels were like 36 and the back was 38 or something. So you’re on the low side.
Great, this is all helpful! Thanks, everyone.
Recently, I had the same issue. When I filled the problem tire, the alert remained. I was told that the alert was triggered by one that was low, but the alert persisted because all were slightly low and needed to be raised to 35-36. They filled them, and the alert stopped; by the way, I was told that there is no reset.
Had the same issue last week with the rear left tire. Pumped everything up back to 35, but the alert remained. Did a visual check and found a nail embedded in the tire. So yeah, it may be a bug, but it may also be a nail.
@Avery
Yeah, if one tire drops significantly all by itself, there is definitely a nail or screw in the tire (or a bent rim).
How do people get a low tire pressure alert and think, “Well it can’t be because the tires are low”.
Just leave some buffer if you inflate during really cold temperatures …when the temperature rises afterwards, that air will expand, and you might have overinflated tires at that point. At least, I’m pretty sure someone wiser than me said that at some point. 
@Sidney
That’s a good point. Thanks.
Double-check the correct pressure for the tires you have. That certainly seems low to me, at least for the OEM tires that are on my 2023 SEL.
Fill to 40 PSI then reduce to 37 or 38 when the error clears.
Check if you have a puncture. I thought mine was due to cold weather but turned out to be a screw and needed a patch.