Ok, one of my headlights doesnt come up and i just got a motor that i know worked. i swapped it out and it still doesnt come up. My dad put my terminals on backwards and with the headlight switch off, BOTH headlights came up. Turned the headlight switch on and BOTH headlights went down. We switch the terminals back and turned the lights on, and ONLY the left one was working again. Can somebody please explain what the heck is happening?