Electric Problem With Swtich on Door

I am having a problem with the switch that trigers the door and cabin lights. I am refering to the button type thing near the door hing. When the doors are close the light sometimes does not go out. I figured out that it was that button or whatever you call it near the door hing that tigers on and off of the cabin and door light. COuld anyone help me to figure out how to get it fixed. Or what I need to get or do to have it fix replaced or what.. I don't want to pay big time shop fees and I have a Haitian friend who is going to help me out on it but I just want to know more about the part ect and what to do.

adjust it, if the adjustment doesnt work then replace it.