I view the TPMS system as a warning system for inflation pressure changes, not for accurate pressure readings. Inflation pressure varies considerably with temperature, so the inflation pressure can change considerably while driving. Every couple of months, I check the inflation pressure with an accurate pressure gauge after our i3 has been parked overnight. I either release or add air to attain my inflation pressure goal. I depend on the TPMS system to warn me when the inflation pressure of a tire changes relative to other tires which usually indicates a leak.
2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE