2008 GMC Envoy Owner's Manual - Page 363

Tire Pressure Monitor Operation The Tire Pressure Monitor System (TPMS) is designed to warn the driver when a low tire pressure condition exists. TPMS sensors are mounted onto each tire and wheel assembly, excluding the spare tire and wheel assembly. The TPMS sensors monitor the air pressure in the vehicle's tires and transmit the tire pressure readings to a receiver located in the vehicle. The TPMS is designed to alert the driver if a low tire pressure condition exists. If your vehicle has the Driver Information Center (DIC) steering wheel control buttons, tire pressure levels may also be checked through the DIC. See "Tire Pressures" under DIC Operation and Displays on page 3-50. When a low tire pressure condition is detected, the TPMS illuminates the low tire pressure warning light located on the instrument panel cluster. At the same time a message to check the pressure in a specific tire appears on the Driver Information Center (DIC) display. The low tire pressure warning light and the DIC warning message come on at each ignition cycle until the tires are inflated to the correct inflation pressure. Using the DIC, tire pressure levels can be viewed by the driver. For additional information and details about the DIC operation and displays see DIC Operation and Displays on page 3-50 and DIC Warnings and Messages on page 3-53. The low tire pressure warning light may come on in cool weather when the vehicle is first started, and then turn off as you start to drive. This could be an early indicator that the air pressure in the tire(s) is low and needs to be inflated to the proper pressure. A Tire and Loading Information label, attached to your vehicle, shows the size of your vehicle's original equipment tires and the correct inflation pressure for your vehicle's tires when they are cold. See Loading Your Vehicle on page 4-34, for an example of the Tire and Loading Information label and its location on your vehicle. Also see Inflation - Tire Pressure on page 5-64. 5-69