Tire pressure sensor is missing or damaged.
Under the following conditions, the TPMS may not function properly: The sensors are attached to the portion of the valve stem located inside the wheel with a T10 Torx screw. If it is determined that the tire pressure has fallen below this limit, the SJB sends a message to the instrument cluster, which then illuminates the low pressure warning indicator and displays the appropriate message(s) in the message center (if equipped).Īll tire pressure sensors are battery-operated. If the vehicle is stationary for more than 30 minutes, the sensor will enter into a “sleep mode” and stop transmitting.Įach tire pressure sensor transmission is compared against a low-pressure limit (pressure listed on the vehicle certification label minus 25%, which will be about 6 psi to 9 psi). The sensors transmit radio frequency signals to the smart junction box (SJB) approximately every 60 seconds when the vehicle speed exceeds 20 mph (32 km/h). The tire pressure monitor system (TPMS) monitors the air pressure in the four road tires with wheel-mounted tire pressure sensors. SPECIAL TOOLS NEEDED? A TPMS activation tool (204-363) must be used. SUBJECT VEHICLES: Ford Expedition 2011-16 Ford Expedition EL 2011-12 Lincoln Navigator 2011-16 and Lincoln Navigator L 2011-12.