Step by step guide on how an automotive tire pressure indicator system works, this information pertains to most systems.
Step 1 - Sensors are used to monitor individual tire pressure in all tires including the spare. If air pressure in any given tire goes below or above minimum or maximum requirements the warning light will illuminate.
Step 2 - Each sensor gives feedback data, which is then transmitted to the central controller where calculations are performed.
Helpful Information
The LTI (low tire indicator) was devised to help prevent accidents due to low tire pressure. A receiver picks up the signal from the tire transponder and then sends the information across an information bus. These processors then compute information and send a signal to an on board diagnostic center which includes a warning light located on the dash. Some vehicles include integrated remote service like OnStar, that can send a message to a phone when the low tire inductor warning system has been activated.