20-07-2015, 09:17 AM 
	
	
	
		Small wire brush and contact cleaner is what I'd use.
For a loose contact, if its the blade type (I think it is?) just squeeze the socket together slightly with long nose pliers.
	
	
	
For a loose contact, if its the blade type (I think it is?) just squeeze the socket together slightly with long nose pliers.

 
 

