What is a tire pressure monitoring system?
- Date added:
- Tuesday, 18 October 2011
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Answer
Tire pressure monitoring systems (TPMS) warn the driver when a tire is significantly underinflated and is standard equipment on every 2008 vehicle and newer.
There are two types of TPMS, direct and indirect.
Direct uses pressure sensors located in each wheel to directly measure the pressure in each tire and warns drivers when the air pressure in any of their tires drops at least 25% below the recommended cold tire inflation pressure identified on the vehicle placard.
Indirect uses the vehicle's antilock braking system's wheel speed sensors to compare the rotational speed of one tire vs. the others. If one tire is low on pressure, it will roll at a different number of revolutions per km than the other three tires, and alert the vehicle's onboard computer.
