Through Model Year 2010
Tire Pressure Monitoring Sensor
Although additional sensors operating at 433 MHz sensors are available and are used in other applications, they are not interchangeable. Always make sure the correct sensor is being used and be sure to replace the sensor with the correct part number.
Special tools, testers and auxiliary items required
• Tire Pressure Monitor System Diagnostic Tool (J-49225)
Description
On vehicles equipped with tire pressure monitoring, one tire pressure sensor (6) is mounted to each wheel (5) in place of the traditional tire valve stem. Each sensor has an internal battery that lasts up to 10 years. The battery is not serviceable. At the time of battery failure, the sensor must be replaced.
The TPM system operates on a 433 MHz radio frequency. The 433 MHz sensors (1) can be easily identified by the part number.
• Once mounted inside a tire and wheel assembly you are not able to visually see the difference between this sensor and other 315 MHz and 433 MHz sensors. At that point, the Tire Pressure Monitor System Diagnostic Tool (J-49225) , with the scan tool may be used to identify the sensor frequency or the tire can be dismounted allowing visual inspection of the sensor body and part number.
• Do not attempt to install a tire pressure sensor in an aftermarket wheel. If aftermarket wheels are installed and do not contain tire pressure sensors, the system will not function properly and the driver will be continuously notified of a system malfunction
The TPM sensors are designed for original style factory wheels. It is not recommended to install a tire pressure sensor in an aftermarket wheel (This could cause sealing and system performance issues).
1 Metal Washer
2 Seal
3 Nut (with pressed-in washer)
4 Cap (with seal)
5 Sectional Cutaway Of Wheel
6 TPM Sensor
The serviceable components of the tire pressure sensor are:
• Sensor-to-wheel seal (2) and metal washer (1).
• Valve stem cap (4).
• Valve stem core.
• Valve stem nut (with pressed-in washer) (3).
• Any time a sensor is installed on a wheel, a new sensor-to-wheel seal (2), metal washer (1) and valve stem nut (3) must be installed to ensure air tight sealing. A service kit is available.
The valve stem caps and cores are specifically designed for the tire pressure monitoring sensors. Although similar to standard valve stem caps and cores, they are different. The valve stem cap has a special seal inside to keep moisture and corrosion out. The valve stem core has a special nickel coating to protect from corrosion.
Operation
The battery operated tire pressure sensor is both a transmitter and a receiver. The TPM sensor can be forced to transmit by using a special tool such as a TPM-RKE analyzer. Using a TPM-RKE analyzer can take up to a minute to force a transmission from a sensor.
• The TPM-RKE analyzer will not define the mode.
The TPM sensor can be in one of the following operating modes:
• OFF MODE - A new TPM sensor will be in this mode. In this mode the sensor does not transmit periodically on its own. By forcing a transmission from the sensor with the TPM-RKE analyzer, it will change to the STATIONARY MODE. The sensor will also automatically change from OFF mode to the STATIONARY MODE once it experiences a great increase in pressure (i.e. installation into a wheel/tire assembly and then inflated).
• WAL MODE - This is the operating mode the sensor assumes when the vehicle is driven over 15 mph (24 km/h), but only after the vehicle was previously parked for a duration of 18 minutes or greater. In WAL MODE the sensors transmit every 33 seconds and these transmissions contain left/right information that allows the TPM Module to determine sensor location on the vehicle. WAL MODE lasts for the first 10 minutes of consecutive driving, then NORMAL DRIVE mode ensues.
• FACTORY MODE - This is a special case of WAL MODE. If a TPM sensor has just been taken out of OFF MODE, then for the first 3 minutes of the WAL period (10 minutes) the sensors transmit at an accelerated rate of every 10 seconds. After the first 20 drives, then the sensors never again transmit out of FACTORY MODE.
• NORMAL MODE - This is the operating mode the sensor assumes after the first 10 minutes of a drive. In NORMAL MODE the sensors transmit every 66 seconds and cease transmitting left/right information. SERVICE MODE - Once a vehicle stops, the sensors go into SERVICE MODE. After 18 minutes of no driving then the sensors go into the STATIONARY MODE. If the vehicle was stopped for less than 18 minutes and driving resumes, then the sensors go back to the NORMAL MODE.
• STATIONARY MODE - When a vehicle has been stopped for more then 18 minutes, then the sensor is forced into STATIONARY MODE. In STATIONARY MODE the sensor never transmits any pressure information. The sensor leaves STATIONARY MODE and enters WAL MODE when the vehicle is driven above 15 mph (24 km/h).
Each sensor broadcast is uniquely coded so that the TPM module can monitor the state of each of the sensors on the four rotating road wheels. The TPM module can automatically learn and store the sensor's ID while driving "within 20 minutes continuously above 15 mph (24 km/h)" after a sensor has been replaced. The vehicle must be stationary for more then 20 minutes in order to initiate the learning sequence. The TPM module can also learn the sensor ID using the Tire Pressure Monitor System Diagnostic Tool (J-49225) , with the scan tool following the procedure listed in the appropriate diagnostic information.