Tire Monitoring System: Service Precautions
TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: PRECAUTION
1. TIRE PRESSURE WARNING SYSTEM PRECAUTION
(a) When the tire pressure warning light comes on, check the tire pressure and adjust it to the specified value. (The tire pressure warning light will come on after blinking for 1 minute if there is an open in the tire pressure warning light circuit.)
NOTICE:
Check the spare tire as well since this system monitors pressure of 4 tires.
Cold Tire Inflation Pressure:
(b) When the tire pressure warning light comes on after blinking for 1 minute, there is a malfunction in the system. Check for DTCs.
(c) Changing the tire pressure warning select switch between "MAIN" and "2nd" allows registration of 2 sets of transmitter IDs. Check the tire pressure warning select switch to see whether the tire is registered in "MAIN" or "2nd".
If the vehicle is driven without selecting the correct switch position, the tire pressure warning ECU and receiver determines that the system is malfunctioning and causes the tire pressure warning light to come on after blinking for 1 minute.
(d) It is necessary to register the transmitter ID in the tire pressure warning ECU and receiver after replacing the tire pressure warning valve and transmitter and/or tire pressure warning ECU and receiver Registration.
(e) When replacing the tire pressure warning ECU and receiver:
(1) Using the Data List, read the transmitter IDs registered in the ECU and make a note of them before removing the tire pressure warning ECU and receiver.
(2) Register the transmitter IDs after installing a new tire pressure warning ECU and receiver.
(f) When replacing the tire pressure warning valve and transmitter:
(1) Take a note of the 7-digit number (transmitter ID) written on the new tire pressure warning valve and transmitter when replacing the old one. Register the transmitter IDs in the tire pressure warning ECU and receiver after replacing the tire pressure warning valve and transmitter and installing the tires and wheels on the vehicle.
NOTICE:
The transmitter ID is written on the tire pressure warning valve and transmitter. It will be unable to be read after installing the tire pressure warning valve and transmitter on the tire and wheel. Therefore, take a note of the transmitter ID before installing the tire pressure warning valve and transmitter.
(g) Tire and wheel replacement or tire rotation:
* After the tires or wheels are replaced with a new tire pressure warning valve and transmitter, it is necessary to register the transmitter IDs.
* After the set of the tires and wheels are replaced, be sure to select the tire pressure warning select switch.
* It is not necessary to register the transmitter IDs after tire rotation is performed.
* After dropping the tire pressure warning valve and transmitter into the tire, disengage the bead from the wheel.
NOTICE:
Be careful not to damage the tire pressure warning valve and transmitter because of interference between the sensor and tire bead.
* The initialization is necessary to reset the warning threshold in accordance with the variant tire pressure settings due to the tire types.
(h) When replacing the tire pressure warning ECU and receiver and the tire pressure warning valve and transmitters, it is necessary to perform the initialization Initialization after the registration Registration.
(i) Precautions about the tire pressure:
* Tire pressure decreases naturally.
* In winter, tire pressure may decrease due to low ambient temperatures (tire pressure decreases by approximately 10 kPa (0.1 kgf/cm2, 1.45 psi) for every 10°C (50°F) drop in the ambient temperature).
* Therefore, the tire pressure warning system is more likely to indicate a warning if the tire pressures are not adjusted appropriately. If the daily temperature variation is large, pressurize the tires high so that the tire pressures are suitable under cold conditions. As a result, incorrect tire pressure warning operation should decrease.
2. IN CASE OF TIRE AND WHEEL REPLACEMENT
(a) When tires and wheels are replaced, always ensure that each transmitter ID is correctly registered.
(b) Before removing the tires from the disc wheels or reinstalling the tires to the disc wheels, be sure to follow the correct procedures for removal and installation of the tire pressure warning valve and transmitter. Failure to do so may cause the tire pressure warning valve and transmitters to break Removal.
3. INITIALIZATION PRECAUTION
(a) Initialize the tire pressure warning system after any of the following is performed:
* Replacing the tire pressure warning ECU and receiver and/or the tire pressure warning valve and transmitter
* When rotating tires on vehicles with differing front and rear tire inflation pressures
* Replacing tire(s) with different tire pressure
HINT
The tire pressure warning system will not operate properly if it is not initialized Initialization.
4. FAIL-SAFE FUNCTION
(a) When a system malfunction occurs in the tire pressure warning system, the tire pressure warning light comes on after blinking for 1 minute.
(b) The result of this malfunction diagnosis is stored in the tire pressure warning ECU and receiver.
5. CHECK TIRE PRESSURE AFTER REPAIRS
(a) After repairs confirm that the actual tire pressures are displayed in the Data List Scan Tool Testing and Procedures.