Tyre Pressure Monitoring System


From 2014 onwards all new vehicles sold in the EU are required by law to have a Tyre Pressure Monitoring System (TPMS)fitted as standard. TPMS is an active system that measures tyre pressure and sends it to a central computer. Electronic circuitry mounted inside the valve stem, measures the tyre pressure reporting back to the control unit of the vehicle.  There are two forms TPMS can take Direct or Indirect. All Tyre and Service Superstore employees are fully trained in the operation  of all areas of TPMS.

Direct TPMS:

Direct TPMS methods use pressure sensors to measure pressure in each of the four tyres. Then these sensors transmit the pressure data via a wireless RF transmitter to a central receiver. The receiver communicates to a display that informs the driver which tyre is underinflated. The tag in each wheel is designed to send a warning signal when a tyre's pressure drops below its specified safety level. Tyre-mounted pressure sensor is shown in Figure 1. Under-inflation has been cited as a cause of tyre failures such as tread separation or tyre blowouts. It is also responsible for shortening tyre life and reducing fuel economy.

Indirect TPMS:

Indirect systems employ wheel speed sensors on a vehicle's anti-lock brake (ABS) system to track each tyres rotation. The premise is that under-inflated tyres have a smaller radius, resulting in a higher rotational speed compared with a fully inflated tyre. The sensor is supposed to detect the faster rotation, and the system alerts the driver. In practice, this change in radius is small, making indirect measurement less reliable than direct pressure measurement.

Technical features

 

How to keep your tyres properly inflated:

  1. Check tyre pressure at least once a month and before going on long trips. Since temperature affects tyre pressure, it is best to check tyres when they are cold, i.e. haven't been driven on for at least three hours.
  2. Fill your tyres with the pressure recommended on the tyre label, located on the drivers door frame, sill or edge.
  3. If you have any questions about your tyres or maintenance, check your owners manual or consult your local Tyre and Service Superstore Branch.


Questions and answers:

Q:  WHY IS PROPER TYRE INFLATION IMPORTANT:

A:   Keeping your tyres at the recommended pressure is essential for the safe and efficient operation of your vehicle. Safety experts estimate that 25 percent of automobiles are running on tyres with lower than recommended pressure. Properly inflated tyres run cooler, last longer, and improve fuel economy.

Q:   WHY DOES TYRE PRESSURE CHANGE:

A:   Many factors affect tyre pressure, and that is why it is so important to check your tyres at least once a month and before going on long trips. Tyre pressure can decrease due to tyre damage, slow leaks, or changes in outside temperature. For example, when the weather changes, your tyre pressure changes too. For every drop of 10 degrees Fahrenheit in temperature, your tyres lose 1 psi. Tyres also deflate naturally over time, as much as 1.5 psi per month.


Q:   HOW DOES THE NEW TYRE PRESSURE MONITORING SYSTEM WORK?:

A:   Sophisticated sensors in the automobile continuously monitor tyre pressure, and the warning light goes on when a tyre is 25 percent or more below the appropriate tyre pressure.

Q:   WHEN WILL THE NEW TYRE PRESSURE MONITORING SYSTEM BE AVAILALBLE?:

A:   The U.S. government, through the National Highway Traffic Safety Administration (NHTSA), requires Tyre Pressure Monitoring Systems on all passenger cars and light trucks by the 2008 vehicle model year. Check your owners manual to see if your vehicle is equipped with a Tyre Pressure Monitoring System. Many models have already been equipped with a system.

Q:   IF THE WARNING LIGHT GOES ON AND OFF, WHAT DOES THAT MEAN?:

A:   On cold mornings, the warning light may illuminate and then extinguish as tyre pressure increases due to driving or outside air temperature increases. Additionally, if the warning light goes on and off, a malfunction in the system is indicated by a blinking light (for a period of 60 seconds to 90 seconds). After blinking for the brief time, the warning light can remain on. You should then contact your dealer for a system inspection.

Q:   HOW SOON DO I NEED TO FILL MY TYRES IF THE LIGHT GOES ON?:

A:   Please heed the warning light and check your tyres as soon as possible.

Q:   DOES THE WARNING LIGHT ALWAYS MEAN THAT THE TYRE PRESSURE IS LOW?:

A:   The warning light may indicate a system malfunction requiring a dealers attention. If the warning light flashes before it is continuously on, but the tyre pressure is found to be within the appropriate range, contact your dealer for a system inspection.

Q:    WHAT ELSE DO I NEED TO DO FOR TYRE SAFETY?:

A:    The Tyre Pressure Monitoring System is a tool to keep you informed about low tyre pressure, but it is no substitute for regular tyre maintenance. Check your tyre pressure at least once a month and before going on long trips. Consult your owners manual on replacing a tyre or using a spare tyre.

Find Out More:

http://en.wikipedia.org/wiki/Tire-pressure_monitoring_system