Does anyone know how the TPMS system works?

Im running BFG 33’s and like to run em at 30lbs. With the cold in the mornings the warning indicators will go off until the tires warm up and the pressure goes back to ~30psi.

my question is why would only 3 of the 4 indicators be active?

 

Because that 4th one isn’t low enough pressure that the computer will show it in orange yet. It’s probably 27.8psi where the other ones are below 27.4 (arbitrary numbers, but used to show digit resolution).

Your dash display just doesn’t show these digits, but just integers.

I bet if you jumped out and let out a tiny bit of air from the fourth, it would turn orange.

 

Or it was initialized at a slightly lower pressure than the rest so the threshold pressure is lower.

 

Ahh good thoughts. Thank you both for the feedback

I was wondering if I had a calibration issue but thresholds make more sense