2004 GMC Envoy Owner's Manual - Page 297

Indicator Light The indicator light on the inflator switch in the rear passenger compartment also serves as an indicator for internal system error. If the indicator light is flashing without the load leveling function or the inflator being active, turn off the ignition. The next day turn on the ignition and check the indicator light. The vehicle can be driven with the light flashing, but if it is you should have the vehicle serviced as soon as possible. Towing a Trailer {CAUTION: If you do not use the correct equipment and drive properly, you can lose control when you pull a trailer. For example, if the trailer is too heavy, the brakes may not work well - or even at all. You and your passengers could be seriously injured. Pull a trailer only if you have followed all the steps in this section. Ask your dealer for advice and information about towing a trailer with your vehicle. Notice: Pulling a trailer improperly can damage your vehicle and result in costly repairs that would not be covered by your warranty. Always follow the instructions in this section and check with your dealer for more information about towing a trailer with your vehicle. To identify the trailering capacity of your vehicle, you should read the information in "Weight of the Trailer" that appears later in this section. Adding a Snow Plow or Similar Equipment Your vehicle was neither designed nor intended for a snow plow. Notice: Adding a snow plow or similar equipment to your vehicle can damage it, and the repairs would not be covered by warranty. Do not install a snow plow or similar equipment on your vehicle. 4-55