When do I need to reset the TPMS After maintenance work, when the vehicle tire pressure indicator light is on, the tire pressure must be reset, and the TPMS indicator light is off. After the tire pressure is too low or leaks, replace or install the tire pressure monitoring device, replace the tire, the sensor is damaged, and the TPMS must be restarted. How to use EL50448 TPMS Relearn Tool You need 1 x 9 V battery to work. Put the vehicle in TPMS learning mode. (Car horn twice) Start in front of the driver and bring the device closer to the valve. Press the button. The horn will be blown. Rest TPMS in the following order: left front, right front, right back, left back. After all sensors are reset, the car beeps twice, and the TPMS learning is completed. How do I put my car into TPMS relearn mode Place the gear in the P position. Use Cruise to select TPMS Re-Learn mode in the Dashboard settings. The horn beeps twice and the TPMS indicator flashes, indicating that it has successfully entered the learning mode. If present, the front left tire (LF) is displayed in the message center. Applicable models: Almost all GM series vehicles from 2010-2019 If you buy an aftermarket sensor with an incorrect frequency, it will not work. It is suitable for cars and light trucks, not for heavy trucks.