1999 Cadillac DeVille Owner's Manual - Page 304

yellowblue 2. Turn the headlamp housing socket counterclockwise to unlock the socket from the lamp housing. 3. Disconnect the socket from the harness by separating the locking clip. 4. Install the new bulb and socket to the wiring harness connector. Make sure that the harness is locked to the bulb socket. 6-34