Why TPMS delay?

[adrianL]

One has to drive a short distance before getting any TPMS pressure readings. Does anyone know why this should be?
I understand that the pressure will increase as the tyre warms, but surely setting off not knowing that perhaps one tyre is significantly soft is a bad idea.
Does anyone know the thinking behind this delayed reading - and can anything be done to alter it?

M3P- 2019Lonion

 

[Mash]

Nothing can be done about it - without centrifugal force they just in a sleep mode to save the battery and prolong it's life 10-20 times.

 

[Perscitus]

Within spec, industry best practice regardless of whether your car is equipped with older or newer (bluetooth) TPMS sensors.

With recent 2022.20.x builds at least you can finally completely reset the sensors to force a position re-learn (after say a tire rotation). Up until this year, TPMS position was not resettable so if you rotated say FR to RL or RR to FR, the TPMS indications would be wrong (staying where they were originally registered at the factory).

The other feature most miss is you can also set your own default/nominal pressure which will be used as a reference for TPMS alerts. Service Menu option for resetting TPMS allows for a 'normal' cold pressure relearn.
So for example if you prefer 3.1 vs 2.9 bar as your nominal pressure, you can inflate the tires cold to 3.1, go for a short 25-32km/h drive so the sensors activate and give readings, park to make the reset setting visible, and force a relearn, drive off and done.

 

[adrianL]

Many thanks Perscitus & Mash, I had no idea they required a burst of centrifugal force or had a sleep mode. I'm not bothered about setting personalised base readings, so I guess a quick eyeball before setting off and look at the actual reading soon after is the best I can do.
Appreciate the help!

 

[Perscitus]

Highly recommend a portable inflator so you can check/adjust the cold pressure easily anywhere and with seasonal changes. Really important with heavy EVs, much more than any ICE car.

They are accurate enough that you can use them to equalize pressures once a month or quarter and almost ignore the TPMS aside from noticing leaks, etc.

Oasser Air Compressor Portable Mini Air Inflator Hand Held Tire Pump 2000 Battery Digital LCD for Car Bicycle Tires Inflatables 12V 110V AC DC P1S https://a.co/d/0a61uO4

 

[Mash]

There are small battery powered auto inflators like the one from Xiaomi. It's too slow and too small battery, to inflate from zero all tires, but good enough for corrections.