The Tire Pressure Monitoring System (TPMS) is a warning system that is standard on vehicles produced in the United States since 2008. TPMS uses sensors located inside each wheel to continuously monitor the pressure in your tires. Data from these sensors is sent wirelessly to a computer control module. When the air pressure falls below a designated threshold, the computer triggers a warning light that shows up on your dashboard display.
Over time, the batteries in the TPMS sensors will become depleted. When this happens, new sensors must be installed. After installation of new TPMS sensors, a technician usually needs to reset the system, to introduce the new sensors to the computer.
Sometimes, a TPMS sensor is “forgotten” by the computer, leading to a system error. In that case, the technician must help the computer to “relearn” in a similar way that you might press the reset button for a computer mouse to reconnect through bluetooth.
The TPMS reset, therefore, is necessary anytime the sensors are unable to communicate with the vehicle computer.
If your TPMS light is flashing, the air pressure in one or more of your tires has dropped below the threshold set by the vehicle manufacturer, usually somewhere around twenty five percent below the normal PSI specification. If your tires are supposed to be inflated to 35 PSI, the TPMS light will come on around 26-28 PSI, depending on the manufacturer.
If, on the other hand, the TPMS light comes on and remains steady, the indication is that there is a problem with the system itself. This is often due to dead batteries in the sensors, but can also be caused by the computer failing to detect the sensors.
TPMS reset is an electronic function aimed at reintroducing your vehicle’s computer to the sensors inside the wheels. On many vehicles, this reset (or “relearn”) can be done automatically by simply driving the vehicle after the TPMS sensors have been replaced. Other vehicles require a special process that requires a technician to connect a special diagnostic scan tool to your vehicle’s data port located below the dashboard on the driver’s side of the vehicle or with a special wireless scanner that can communicate with the individual sensors.