Tires Make the World Go Round (Part 3 of 3)

Tire PMS - Rock, Paper, Car

T.P.M.S. Is it your cars time of the month?

What is T.P.M.S.? Tire Pressure Monitoring System. The TPMS is an electronic system designed to monitor the air pressure inside the tires on various types of vehicles. The system is also sometimes referred to as a tire-pressure indication system (TPIS). These systems report real-time tire-pressure information to the driver of the car, either via a gauge, a pictogram display, or a simple warning light.

Why do I need a T.P.M.S.? The Firestone Recall in the United States in the late 1990s, which was attributed to more than 100 deaths from rollovers following a tire tread-separation, pushed the Clinton Administration to publish the TREAD Act. This act mandated the use of a suitable TPM technology in order to alert drivers of a severe under-inflation condition of their tires. This act affects all vehicles weighing less than 10,000 pounds and sold after September 1, 2007.

How does the system work? Direct-sensor TPMSes use physical pressure sensors inside or outside each tire and a way of processing and sending that information to the vehicle's instrument cluster. These systems can simultaneously identify under-inflation in all four tires and in any combination.

Typically, tire pressure monitoring systems operate with four or five battery-powered transmitter-sensors, one RF (radio frequency) receiver, and some other satellite hardware which can perform the function of identifying which tire has the inflation problem. Each tire-pressure sensor periodically sends a message regarding pressure status, or it can poll the pressures continuously. Note: These batteries are not replaceable; the whole sensor unit must be replaced.

Indirect style TPMSes do not use physical pressure sensors. They measure the "apparent" air pressure, by monitoring individual wheel rotational speeds, and other various signals available outside the tire itself. Most indirect TPMSes use the fact that an under-inflated tire has a slightly smaller diameter than a correctly inflated tire and therefore has to rotate at a higher speed to cover the same distance as the correctly inflated tire.

A TPMS helps to improve vehicle safety, and aids the driver in maintaining proper vehicle tire pressures. (Which actually is a new California Law -2010.) Properly maintained tires help with vehicle safety, performance and economy. In the U.S., the National Highway Traffic Safety Administration (NHTSA) has estimated that every year, 533 fatalities are caused by tire defects in road accidents. Adding TPMS to all vehicles could avoid 120 of the 533 yearly victims and spare as many as 8,400 injuries every year. (Don’t you love statistics?)

On the maintenance side, it is important to realize that fuel efficiency, and tire wear are severely affected by under-inflation. According to NHTSA data, tires leak air naturally and over a year a typical new tire can lose from 3 to 9 psi, roughly 10%, or more, of its initial pressure. Environmental conditions also affect tire psi.

Water Star Motors has the specialized equipment needed to test and repair your TPMS. All of these systems with transmitters have a battery that wears out in 7-10 years. These batteries are not replaceable. Is it time to replace your sensors with new ones?

Some of these systems are excellent and need little care. Others are more problematic. No problem, we can take care of all your needs in the TPMS arena!