TPMS is an automated system that monitors the air pressure in a vehicle's tires.

TPMS - Tire Pressure Monitoring System

As part of the effort to increase awareness of the need to maintain proper tire pressure, the U.S. government has taken steps to make it easier for drivers to be aware of potentially unsafe low pressure in their tires. As of the 2008 model year, the National Highway Traffic Safety Administration (NHTSA) now requires that all passenger cars and light trucks feature the Tire Pressure Monitoring System (TPMS). In conjunction with the new requirements, the Alliance of Automobile Manufacturers (AAM) has initiated a consumer safety campaign focusing on the importance of maintaining proper tire pressure.

"Visit us in person, or shop online, and we'll show you all the TPMS options for your vehicle."

TPMS is an automated system that monitors the air pressure in a vehicle's tires. When air pressure in one or more tires drops 25 percent or more below the correct pressure, a warning indicator alerts the driver. TPMS typically delivers these alerts to the driver through one of two types of warning lights on the dashboard.

1. The first uses the official TPMS symbol, which is a cross-section of a tire with an exclamation mark in the center.

2. The second is a top-view graphic image of a car that indicates which tires are low.

Tire pressure is monitored through one of two methods: direct or indirect. Direct TPMS monitors the actual air pressure inside each tire via a sensor mounted within the tire. Indirect TPMS measures tire pressure by monitoring the speed and rotation of each individual wheel. When a significant variation in speed and rotation is detected in one or more wheels when compared with the others, it is often an indication of underinflation. This information is then transmitted to the vehicle's on-board computer, and the driver is alerted.

TPMS Car Schematic

However, while TPMS systems offer increased safety to drivers through low pressure warnings, they are not meant to be a substitute for proper tire pressure maintenance. Be sure to read our article on the importance of correct air pressure for more in-depth information.

Even though TPMS has only recently become standard for all vehicles, a number of older models already have them installed. Approximately 20 percent of 2006 vehicle models came pre-equipped with TPMS, and that number increased to 70 percent in the 2007 model year. If you are unaware if your vehicle has TPMS installed, check your vehicle owner's manual. If you don't presently have TPMS on your vehicle, we can help. Discount Tire offers TPMS sensor kits for virtually all vehicles on the road, TPMS rebuild kits, and retrofit kits for vehicles not factory equipped with a TPMS system. We will be happy to install them for you as well. Be sure to visit your local Discount Tire location and inquire about our TPMS kits.

Sources: NHTSA, AAM, Intelligent Tire Conference

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