TPMS-Tire Pressure Monitoring System. This is a monitoring system to give real time alerts to the driver of a vehicle. The air pressure in your tires can be helpful in saving money on gas and maintenance. Checking the TPMS sensor on a regular basis will insure the life of your tires and vehicle in the long run. Anytime you see this sensor light you should stop and fill your tires to the PSI written on the tire.