The tire pressure monitor system is a software driven system. The system uses the existing antilock braking system components (Electronic Brake (and Traction) Control Module (EBCM/EBTCM) and wheel speed sensors), serial data class 2, and instrument cluster to perform the system functions.
The EBCM/EBTCM contains the software to perform the system monitoring functions. The EBCM/EBTCM uses wheel speed data obtained from the wheel speed sensors to detect relative pressure differences of 69 kPa (10 psi). This means that one tire is at least 69 kPa (10 psi) lower in pressure than the other three. The EBCM/EBTCM uses only smooth data. Braking, an acceleration or deceleration of greater than 0.1 g, and/or any ABS/TCS system activity causes the EBCM/EBTCM to stop perform tire pressure monitor system functions. When the EBCM/EBTCM detects a low tire pressure condition the EBCM/EBTCM sends a message to the instrument cluster via the serical data class 2.
The instrument cluster performs two functions related to the tire monitoring system.
| • | Displays the warning message TIRE PRESSURE LOW: CHECK TIRES when commanded by the EBCM/EBTCM, via the serial data class 2. |
| • | Sends the tire pressure monitor system reset command to the EBCM/EBTCM, via the serial data class 2. |
The serial data class 2 is used to send all tire pressure monitor system related information between the EBCM/EBTCM and the instrument cluster.
Tire Pressure Monitoring System Reset
- Set all tires to the manufacturer's recommended pressure.
- Start engine.
- Press the GAGES button on the IP until the TIRE PRESSURE message appears on the instrument cluster message center display.
- Press and hold the RESET button on the IP until the TIRE PRESSURE RESET message appears.
- Release the button, the TIRE PRESSURE NORMAL message appears. The system is now in the autolearn mode.
