What is the difference between direct and indirect TPMS?
Short answer: Direct TPMS uses a pressure sensor in each wheel that reports by radio, while indirect TPMS uses the ABS wheel speed sensors to detect a tire turning faster because it is low.
Direct systems put a battery-powered sensor inside each wheel, usually as part of the valve stem or banded to the wheel. Each sensor measures pressure, often temperature, and transmits to a receiver or module. The vehicle can show individual tire pressures and detect slow leaks precisely.
Indirect systems have no sensors in the wheels. They watch wheel speed through the ABS sensors. An underinflated tire has a slightly smaller rolling diameter and turns faster than the others, so the system flags it. Indirect systems usually need a reset after inflating or rotating tires and cannot show actual pressures.
For service, direct systems need sensor tools, compatible replacement sensors and relearn procedures. Indirect systems mostly need correct inflation and a reset through the vehicle menu or a scan tool. Check the vehicle's service information to see which system it uses.
Tools used for this job
General guidance only. Follow the vehicle and tool manufacturer's procedures, and confirm vehicle coverage on the tool maker's list before buying.