Pop your hood and on the front of the car is a headlight entrance panel. It is right next to the headlights.Get the bulb and take it down to autozone or advance auto parts and they will get you the replacement.
The exterior lights do not have a relay. They are directly turned on by the headlight switch.
headlight switch is bad
Probably a bad headlight switch. Also may be the power feed wire for the headlight switch. Check both.
I would check for any loose connections/obvious things. otherwise replace the headlight switch.
You likey have a bad headlight switch or a crossed wire.
By having a professional repair the problem that has turned the light on. They will reset the light after the repair. This is not a DIY repair.
The radio was wired wrong. Sounds like the hot wire for the radio was connected to the hot wire for the headlight switch.
Cars don't turn off completely, they run on battery power. The headlight switch needs to be turned off.
Immediately after you finished your last drink and turned on the ignition in your car and began driving.
They come on when you turn on the windshield washer, but only when the headlights are turned on.
Sounds like a blown fuse. Quick, cheap and easy fix. If not the fuses are fine then it may be a bad headlight switch.
Check all your grounds. Battery to block and your headlight sockets.