Tire Monitoring System: Description and Operation

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: SYSTEM DIAGRAM





HINT
Each tire pressure warning valve and transmitter send information on the temperature inside the tire, the ID, and the tire pressure.


1. DESCRIPTION OF SYSTEM

(a) Each tire pressure warning valve and transmitter is equipped with a tire pressure sensor and a transmitter and is installed in each tire and wheel. The sensor measures the tire pressure. The measured value and transmitter ID are transmitted to the tire pressure warning antenna and receiver on the body as radio waves and then sent to the tire pressure warning ECU from the tire pressure warning antenna and receiver. If the transmitter ID has already been registered, the ECU compares the measured air pressure value with the standard value. When the value is less than the standard value registered on the tire pressure warning ECU, the warning light on the combination meter comes on.





2. INITIAL CHECK

(a) After the ignition switch is turned ON, the tire pressure warning light comes on for 3 seconds and then goes off.





HINT
If the tire pressure warning light does not come on for 3 seconds, troubleshoot the tire pressure warning light circuit.





3. WHEN TIRE PRESSURE WARNING LIGHT IS LIT

(a) When the tire pressure warning light does not go off, or when it comes on during driving, check the tire pressure. If the tire pressure warning light comes on within several hours to adjusting the tire pressure, the tire may have a slow air leak.

(b) Under the following conditions, the system may not function properly.

Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.

A radio device of similar frequency is used in the vehicle.

A large amount of snow or ice is stuck to the vehicle, especially onto the wheels and around the wheel wells.

The battery of the transmitter has been depleted.

Tires without a tire pressure warning valve and transmitters are used.

Tire chains are used.

If any wheels other than the specified ones are used, the system may not function properly because interference may prevent the radio waves from being correctly transmitted from the tire pressure warning valve and transmitter.

A type of film that affects radio waves is attached to the windows.

Depending on the tire type, the tire pressure warning system may not function properly even though the specified wheels are used.

The tire pressure is abnormally high (absolute pressure: 600 kPa (6 kgf/cm2, 87 psi) or more; relative pressure: 500 kPa (5 kgf/cm2, 72.5 psi) or more).

(c) The average usage life of the grommets of the tire pressure warning valve and transmitter is approximately 10 years, at which time it must be replaced.

If a tire pressure warning valve and transmitter is removed from a wheel, replace the grommets.

(d) After removing and installing the ECU or a sensor, check for DTCs and check that it is a normal system code.

4. FUNCTION OF COMPONENTS