PSI stands for pounds per square inch—it’s the unit of measurement for tire pressure. Ideally, check the tire pressure before driving your vehicle—when the tires heat up, they’ll have higher air pressure.
Keep in mind that the tire pressure for a spare is often much higher than the PSI for the tires on your vehicle. For instance, your car or truck may need its tires inflated to 33 PSI, but the spare should be inflated to 60 PSI.
Consult your owner’s manual to find your vehicle’s TPMS set button. If your car has a newer dashboard screen, scroll through your car’s information options and select “tire pressure monitoring system. " This allows you to reset the system.
All these dramatic changes to the tire pressure should alert the TPMS system, so when the tires are properly inflated the light turns off.
Be aware that this will reset other features in your car, too! It might reset your radio, clock, and other computerized components.
Your mechanic will also remount and rebalance your tires as part of this process.
