TSB: 2018 model year 4Runner vehicles are equipped with a direct-type Tire Pressure Warning System (TPWS). Each tire (including the spare tire*) has a tire pressure warning valve/sensor, and the measured tire pressure data is transmitted to the Tire Pressure Warning System antenna/receiver to the Tire Pressure Warning System ECU. During Pre-Delivery Service (PDS), the tire pressure warning valves/sensors MUST be activated according to the procedure in this bulletin.