Canada - Tire Monitoring System - TPMS Initialization

Bulletin
TSB0630R

Issue Date
October 27, 2003

Market
Canada

Title
INITIALIZATION OF TIRE PRESSURE WARNING SYSTEM

Component
GENERAL INFORMATION

Models
'04 - 05 LS 430

TSB REVISION NOTICE:
November 19, 2004: 2005 model year has been added to applicable vehicles; Text has been revised in Item No. 3, Introduction and Reference section.
The previous TSB should be discarded.

INTRODUCTION:
While the vehicle is in motion, the Tire Pressure Warning System (TPWS) monitors the wheel speed signals that are output by the speed sensors for the brake control system. The system uses the resonance frequency method and the relative wheel speed method to detect low tire pressure in one or more of the tires. The resonance frequency method detects a change in the resonance of the tires that is caused by a low tire pressure based on the total value of the wheel speed signals that are output by the four speed sensors. The relative wheel speed method utilizes the changes in the wheel speeds that occur when the actual radius of a tire decreases due to a low tire pressure. These two methods refer to the normal tire pressure as the standard value when initializing.

To operate the Tire Pressure Warning System under normal conditions, the TPWS ECU must be initialized with the tires at the specified tire inflation pressure.

Tire pressure is set high at the assembly plant for transport and storage to prevent tire flat spots. Therefore, after adjusting all the tires to the standard air pressure, please perform initialization of the TPWS ECU at your dealership prior to delivery.

APPLICABLE VEHICLES:
- 2004 - 2005 model year LS 430 vehicles.






WARRANTY INFORMATION:

INITIALIZATION PROCEDURE:






1. Adjust all tires to the standard air pressure.






2. Turn the ignition switch to the "ON" position with the vehicle stopped. Check that the low tire pressure warning light and "Pressure Initial" appears on the multi-information display.






3. Push and hold the tire pressure warning reset switch for 3 seconds until the low tire pressure warning and "Pressure Initial" light goes off on the multi-information display.

NOTE:
If the low tire pressure warning light doesn't go off, release your finger from the tire pressure warning reset switch and press it once again.

REFERENCE:
While TPWS initialization is in progress, the tire pressure is not being monitored.

Please explain to the customer during vehicle delivery that initialization of tire pressure warning system will be completed after driving the vehicle for 30 to 60 minutes and that the tire pressure is not monitored before the completion of the initialization.