Tire Monitoring System: Description and Operation

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: SYSTEM DIAGRAM





HINT
The tire pressure warning valve and transmitter sends information on the temperature inside the tire, the ID, and the tire pressure.






SYSTEM DESCRIPTION

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 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 in the tire pressure warning ECU, the warning light on the combination meter turns on.





2. INITIAL CHECK

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





HINT
If the warning light does not turn on for 3 seconds, troubleshoot the 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 turns on during driving, check the tire pressure. If the tire pressure warning light turns on within several hours of 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 houses.

* The battery of the sensor has been depleted.

* Tires without a tire pressure warning valve and transmitter are used.

* Tire chains are used.

* When the spare tire is not within the receivable range of the electric waves, a signal may not be received because the spare tire does not rotate. Accordingly, the system may not function properly. If there is a possibility that the tire pressure warning system does not receive a signal from the spare tire, rotate the tire 90 to 270°.

* 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 sensor.

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

* Depending on the tire type, the system may not function properly even if 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 grommet 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 a diagnostic trouble code and verify that it is a normal code.

4. FUNCTION OF COMPONENTS