The final cut of the 8th episode of the Tesla Motors Club Podcast, featuring Balazs Biro, of the prominent Hungarian EV channel Villanyautósok, is now available. You can watch it now on YouTube or listen to it on all major podcast networks.
Looks like a plush ride. I run 45psi. You have zero fear of pinch flats!
Umm...well, those are low pressures. Why that particular one triggers? I don't know. Which part are you not sure about? Haven't ever done the "reset" procedure to get it to be ok with lower pressures, but perhaps if that is done with non-uniform initial pressures it will trigger on the tire that drops (changes) the most (meaning that your system was initiated with that tire at the highest pressure). This is total speculation...but it would be a sensible way to do it...though I'm not sure why someone would WANT to run different pressures in different tires (does make sense to want to run lower pressures in general of course, or if you are at elevation, where the TPMS read low).
In any case, if you want to run those pressures, I would wait for the car & tires to cool, get the pressures perfectly uniform (use a tire pressure gauge for precision of the uniformity if you want), and reset the sensors using the GUI - it's totally straightforward: set your pressures and then do the procedure.
Well it's obvious, make that tire low. LOL. That really has me scratching my head. I know you can reset the TPM, they even mention it changes the factory settings, which in your case might be good.
I'd balance it out and see if you get the backwards message again, then look at the reset procedure.
Individual receiver for each wheel, with some basic logic regarding received signal strength, presumably. It figures it out. When you put on a new set of tires with new TPMS you don't have to do anything - you just slap them on and after a few minutes it comes up and tells you all the pressures (well, it detects a new set of wheels, and you do the TPMS reset, and then it is good).
Seems unlikely that it would try to maintain the same binding during a rotation (without a reset), since it clearly has the ability to determine which wheel is where. I mean, I could be wrong - maybe my pressures were close enough I didn't recognize the pressures had swapped when I rotated - but it wouldn't make any sense, because the system has no need for user input with its capabilities.
Now that you have them all balanced out, I recommend doing the TPMS reset when all the tires are cold and at the appropriate cold pressure you want to run. This process does change the threshold which triggers the low pressure warning.
Anyway, for your original issue, I suspect it may have something to do with the detected change in pressure, not the absolute pressure. Or it could just be random software issues (as you speculated).
Mine have been running low about the same PSI as yours since the 2019.32.2.1 update or maybe even 2019.32. I'm wondering if that contributed because it's certainly not "cooler" temperatures here in Austin.
I suspect the TPMS low-air logic just triggers on one event and that's what it displays. In other words, as soon as one of the tires is low, it doesn't bother to alert you to the others. Rear Left is probably the first one it checked. If you filled that one up, I would anticipate one of the others to then throw an alert, and so on.
I got this same message show up on Saturday night. All 4 tires show as 38 psi. I have my psi normally at 44. Its been that was for about 10 months. It was chilly on Saturday night like around 50 degrees so that is why I thought the psi decreased.
Will the psi go back to normal on its own or should I fill up air in the tires? Thanks.