passenger headlight isn't bright, needs ground maybe?

[mr2poweraw11]

i think the headlight needs ground, i dont know anything about the wiring or other stuff on my car. i know it has to be the wiring, cant be the headlight or the plug, cuz i stole a the plug all smooth from a junk yard and used it up, and i swap headlights and its just the passenger side healight doing that. any homies or G's out there want to help me out it be appreciated. please forgive my stupidness, i haven't been in TN long, and im not a mechanic. thanks.

[MitchB]

The headlight switch provides the ground. The headlights get +12Volts from a relay. A wiring diagram would help you a lot.

Also, rare as it might be, do you have a bad headlamp? Are the low and high beams both dim?

[mr2poweraw11]

thanks, i did replaced the gauge cluster and light switch a long time ago, so i guess i'll start trying to see whats up. i havent checked in a long time, but im sure its only the low that wont brighten up. thanks for your help. now i know where to start looking.