Why do my headlights keep going off and on I bought a new switch in the dashboar

Hello, A faulty headlight relay will cause this issue, but you may also have a wiring issue, a bad grounding cable near the headlights, or, if you have HID headlights, the bulbs may be ready for a change. Shake wires for the switch and headlights, see if anything turns off or on during the process, check your ground cables for cleanliness, and test the relay(s) for the headlights. Let me know if none of those ideas work.