Tire Pressure Monitor (TPM) System
Vehicles can be equipped with either of two types of TPMS:
- Flat Tire Monitor: This is an Indirect system which uses the ABS to detect pressure loss in a tire by comparing the rotating speeds of the individual tires while moving. The Flat Tire Monitor does not use tire pressure sensors mounted on the wheels.
- Tire Pressure Monitor: This is a Direct system which uses tire pressure sensors installed on the wheels to check the inflation pressures of the four mounted tires.