I just put a newer battery in my 06 f150. Was pretty drained (about 9-10 volts). Put it in the truck and hooked the terminals up. Put the charger on. Head lights come on when switch was off and it started making a weird noise from the engine compartment. Any Ideas?

 

Battery needs to be charged to at least 12 volts. Disconnect battery leads, charge, then try again.

 

Could be a bad alternator. They make a weird buzzing sound when they are going out and make your electrical system go haywire. You may have the zone diagnose it for you.