Technicians can identify problems with a TPMS (Tire Pressure Monitoring System) sensor through several diagnostic steps. They start by checking the vehicle's dashboard for any TPMS warning lights. A specialized TPMS scanner tool is then used to detect malfunctioning sensors and to relearn the tire positions if needed. Additionally, technicians may lift the vehicle, dismount the tires, and visually inspect the condition of the TPMS sensors, looking for any signs of damage, such as cracks, corrosion, or breakage.