1999 GMC Envoy Owner's Manual - Page 282

yellowblue High Intensity Discharge (HID) Lighting Headlamps Composite High-Beam Headlamp System 1. Open the hood. CAUTION: The low beam High Intensity Discharge lighting system operates at a very high voltage. If you try to service any of the system components, you could be seriously injured. Have your dealer or a qualified technician service them. Halogen Bulbs CAUTION: Halogen bulbs have pressurized gas inside and can burst if you drop or scratch the bulb. You or others could be injured. Be sure to read and follow the instructions on the bulb package. 2. Remove the black retainer clips by lifting up. 3. Pull the headlamp assembly out. 4. Unplug the electrical connector. 6-32