TPMS — Tire Pressure Monitoring System

TPMS (Tire Pressure Monitoring System) is an electronic system that monitors tire pressure and (on direct systems) temperature. Mandatory in the US on passenger vehicles since 2008 and in the EU since 2014. RVs and trailers often add aftermarket TPMS with external valve-cap sensors.

Two types: direct (sensor inside the tire reports pressure and temperature precisely) and indirect (estimates from ABS wheel-speed). For RVs, direct TPMS is preferred — it catches slow leaks and overheating tires before a blowout. Popular aftermarket systems: TST 507, TireMinder, EEZ RV. Especially important in the US and Australia where hot-weather highway runs in a 4-tonne RV stress tires hard.