My headlights only come on when you hold the dimmer switch when dimmer switch is realeased headlights go off why

Holding dimmer switch back is a way of signaling other drivers with your head lights while head lights are in the off position. Sounds like you have either a blown fuse, faulty head light relay or faulty light switch. If it was mine I would check all fuses first then test the light switch for in coming and out going power. Do your running lights come on but just not your head lights when switch is turned on? If so I would check relay.

In some cases the multifunction switch will go bad or a wire burn out..

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