TPI is an indirect tire pressure monitoring system that detects underinflation in one or more tires using wheel speed signals, rather than in-wheel sensors. It alerts drivers to low tire pressure issues, which account for 75% of flat tires and are a common cause of vehicle breakdowns. Underinflated tires reduce fuel economy by 1.5% for every 0.2 bar underinflation and decrease tire lifespan by 15%, while approximately 20% of passenger cars have underinflated tires. TPI helps improve safety, economy, and the environment by reducing tire wear and fuel consumption through correct tire inflation.