i would like to know why one will be bright and the our will be low and they have both been change and the will change side to witch one that is bright and they some times both work

 

Welcome to the site, most common is the ground wire is loose or the connector is corroded or damaged, sometimes the heat will melt the plastic

 

Welcome to the site

X2 on the grounds also just had a member that found a broken/loose wire at the head lamp connector.

 

If I read it right if you swap sides the dim light changes to the other side, if that is true I would try a different lamp. Even though it works sometimes there could be a poor connection in the lamp base. I hope this helps.