Install the bulb with dielectric grease and use the same grease on the connectors. Install and turn on lights. Bang on headlamp until it comes on. I do this every day since I got my front end fixed. When you close the hood the bulbs may shift and not light up. Sometimes mine go out while driving, I've gotten the parking brake-seatbelt off-door open-lean over and bang technique down to a 22 second tallent for stop lights.