Description: For GM vehicles equipped with a 315 or 433 MHz Tire Pressure Monitoring (TPM) system, a "Sensor Relearn Procedure" must be performed after tire rotation remote lock receiver module or tire pressure sensor replacement. This relearning process can be performed using the special tool EL-50448. Also applies to 2014 GM models Tire pressure sensors on 2012 and later models can only be read using certain designated diagnostic tools. Before the tire pressure monitoring system works normally, the body control module will record the ID information of each position in the tire pressure sensor; after replacing the tire or wheel speed sensor, use the following method to read the tire pressure sensor. For the specific method, please refer to the following: Step 1 - Enter the tilt mode and put the shift lever to " After the learning is completed, the turn signal light will be on for 3 seconds and the horn will beep twice.