Tire Monitoring System: Description and Operation

1. DESCRIPTION OF SYSTEM
a. A transmitter equipped with an inflation pressure sensor is installed in a tire wheel assembly. The sensor measures the tire inflation pressure and the measured value is transmitted to an antenna on the body as radio signals and then sent to a receiver from the antenna. When the value is less than the the standard value registered in the receiver, a warning light in the combination meter lights up or blinks with alarming chime.

2. IN CASE WHERE TIRE PRESSURE WARNING LIGHT IS LIT
a. When the warning light does not go out, or when it lights up or blinks with alarming chime during drive, check inflation tire pressure. If the warning light is lit even though the tire inflation pressure is correctly adjusted, the tire could be punctured or the tire pressure monitor valve sub-assembly may be failed.
b. If the warning light is lit during high speed driving, it may go out when the speed is decreased to intermediate or lower speeds (The pressure-increase-indicated-speed or less). (If the vehicle is driven at higher speeds again, the warning light will light up again. Therefore, increase the air pressure to the specified value prior to high speed running.)
c. The actions to be taken when the warning light is lit are different between the vehicle with normal tires and the one with run flat tires.
d. Under the following conditions, the system may not function properly.
- The areas, facilities or devices that use similar radio frequencies are located in vicinity of the vehicle.
- A radio device of similar frequency is used in the vehicle.
- A lot of snow or ice is stuck to the vehicle, especially onto the wheels and around the wheel houses.
- The battery of the sensor has been depleted.
- The tires without tire pressure monitor valve sub-assembly are used.
- Tire chains are used.
- Although the tires with inflation pressure sensors are used, another tire set has been selected by the select switch.

HINT:
- If any other wheels than the specified ones are used, the system may not function properly because the radio waves are differently transmitted from the inflation pressure sensor.
- Depending on the tire type, the tires may not function properly even though the specified wheels are used.

e. When the warning light is lit for the wheel used that has been for 5 years or more, and if the air is leaked from the part where the valve is installed, tightening the tire valve nut may stop the light warning.

3. HANDLING PRECAUTIONS
a. After removing and installing an ECU or a sensor, output a diagnosis code and check that it is a normal code.

4. IN CASE OF TIRE AND WHEEL REPLACEMENT OR TIRE ROTATION
a. When tires and wheels are replaced, register the transmitter ID without fail.
b. Because no tire pressure monitor valve sub-assembly is attached to the spare tire, the tire pressure warning light remains lit when the spare tire is used due to tire rotation.