1999 GMC Yukon Owner's Manual - Page 321

yellowblue Center High-Mounted Stoplamp (CHMSL) The individual bulbs in the CHMSL are not replaceable. See your dealer for assistance. 4. Remove the screws from the bulb retainer and take the bulb retainer off of the lamp assembly. Rear Lamps 1. Open the tailgate or rear doors. 2. Remove the two black plastic plugs from the rear lamp assembly access holes. 3. Remove the two rear lamp assembly screws inside the fender and pull out the lamp assembly. You may want to use a magnetic screwdriver when removing the screws. 5. Pull the old bulb straight out of the socket. 6. Put in a new bulb and push it straight in until it is tight. 7. Replace the bulb retainer. 8. Replace the rear lamp assembly and tighten the screws. You may want to use a magnetic screwdriver when installing the screws. 9. Close the tailgate or rear doors. 6-41