Operation CHARM: Car repair manuals for everyone.
Home >> Lexus >> 2009 >> IS F V8-5.0L (2UR-GSE) >> Repair and Diagnosis >> Steering and Suspension >> Wheels and Tires >> Tire Monitoring System >> Service Precautions

Tire Monitoring System: Service Precautions








TIRE PRESSURE MONITORING: TIRE PRESSURE WARNING SYSTEM: PRECAUTION

PRECAUTION

1. TIRE PRESSURE WARNING SYSTEM PRECAUTION





(a) When the tire pressure warning light, and master warning light come on and "LOW TIRE" appears on the multi-information display, check the tire pressure and adjust them to the specified value. (The tire pressure warning light will come on after blinking for 1 minute if there is a malfunction in the tire pressure warning light circuit.)
Cold Tire Inflation Pressure:





If the vehicle is to be driven at sustained high speeds of above 160 km/h (100 mph), in countries where such speeds are permitted by law, inflate the front and rear tires to 310 kPa (3.1 kgf/cm2, 45 psi) provided that it does not exceed the maximum cold tire inflation pressure molded on the tire sidewall.

(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) Exchanging tires and wheels as a set
Changing the tire pressure warning select switch (satellite switch) between "MAIN" and "2nd" allows 2 sets of transmitter IDs to be registered. When switching to a second set of tire and wheels, it is first necessary to register the second set of tire pressure warning valve and transmitter IDs under "2nd".
Once registered, the appropriate set of transmitter IDs for either set of tires and wheels can be selected using the tire pressure warning select switch (satellite switch).
Prior to troubleshooting the tire pressure warning system, check to make sure the correct set of transmitter IDs is selected.
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 IDs in the tire pressure warning ECU and receiver after replacing a 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 a tire pressure warning valve and transmitter:
(1) When replacing a tire pressure warning valve and transmitter, each ID numbers of tire pressure warning valve and transmitters must be registered. Even if only one tire pressure warning valve and transmitter is replaced, the ID numbers of the all the tire pressure warning valve and transmitters must be registered again. Record all existing ID numbers before beginning the process to enter new ID numbers.
(2) 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.




NOTE:
The transmitter ID is written on the tire pressure warning valve and transmitter. It will be unable to be read after installing the tire onto the wheel. Therefore, take a note of the transmitter ID before installing the tire onto the wheel.

(g) Precautions about the tire pressure:
- The tire pressures decrease naturally.
- In winter, tire pressure may decrease due to low depending on the ambient temperatures (tire pressure decreases by approximately 10 kPa (0.1 kgf/cm2, 1.5 psi) for every 10°C (50°F) drop in the ambient temperature).
Therefore, the tire pressure warning system is more likely to operate if the tire pressures are not adjusted appropriately. If the daily temperature variation is large, add enough pressure to the tires so that the tire pressures are suitable under cold conditions. As a result, unnecessary tire pressure warnings 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 a tire from a wheel or reinstalling the tire to the wheel, be sure to follow the correct procedures for removal and reinstallation 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) It is necessary to perform initialization Initialization after registration Registration when any of the following is performed:
- Replacement of the tire pressure warning ECU and receiver and/or a tire pressure warning valve and transmitter.
- Replacement of tires with those that require a different tire pressure.
Initialization is necessary to reset the warning threshold in accordance with the tire pressure requirements of various tire types.
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 and master warning light comes on after blinking for 1 minute, and "CHECK SYSTEM" will appear on the multi-information display to inform the driver of the system failure.
(b) The result of this 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.
pro multis · About Operation CHARM