I recently bought a 2002 tacoma. Didn't realize until I got it home it was missing the headlight relay, so of course the headlights don't work. I went to a toyota dealership and got a relay. After putting in a relay, the headlights came on but won't shut off. Any ideas?

I'd say its your switch,The relay is being energized when it shouldnt.So eithersomething is shorting it to energize it at the relay point or the switch is constantly on.