Tyson Boyer: Hi! I am Tyson Boyer with Dill Air Controls; today I'm going to discuss why your tire-pressure monitoring light is frequently illuminated on the dash in the fall or when the temperature changes significantly.
When the weather changes, your vehicle goes through changes as well, this is very common in the fall when large drops in air temperature result and decreases entire air pressure which can cause the light to come on. The National Highway Transportation Safety Administration introduced Federal Mortar Vehicle Safety Standard 138. This rule started the phase-in of tire-pressure monitoring systems in 2005 and mandated 100% compliance on passenger and light truck vehicles sold in the United States weighing 10,000 pounds or less by September 1, 2007. The intent of this system is to protect the driver and occupants from driving on severely under-inflated tires.
When your tire's air pressure changes the performance and handling of your vehicle does too. Have a look at the side wall of the tires; it is sometimes very difficult to see an under-inflated tire. But think of it as sleeping on half inflated air mattress or playing basketball with the ball that is flat. Under-inflated tires will result in poor vehicle handling and lower fuel economy. When the pressure drops 25% or more below the vehicle's cold tire inflation pressure, the TPMS light will illuminate on your dashboard. It is your responsibility to react to the warning light by checking your air pressure and adding air if necessary.
If this light is flashing when you start your vehicle, then the system is not functioning correctly. This could be because the battery and more of the tire sensors is dead. Visit your local tire dealer to have the system diagnosed which could require installation of a new tire pressure sensor; keep in mind; your tires lose their pressure and approximately 1 to 2 PSI per month. If you have not checked your air pressure in two months, you may be 2 to 4 PSI low. At the change in air pressure of 3 to 4 PSI due to a change in the temperature during the fall or winter season and this activates your tire pressure warning light. For approximately every 10 Fahrenheit of ambient temperature change, your air pressure will increase or decrease by 1 PSI. To minimize the chance of your tire pressure light coming on as the temperature decreases, be sure to have your authorized tire and service center inspect and adjust your tires on a monthly basis or when your tire pressure monitoring light comes on. To maintain the system be sure the valve components are replaced when you purchase new tires, because the materials wear out over time just as your tires do; your tires maintain your vehicle's contact to the road, don't neglect them or your vehicle's performance and handling maybe compromised.