tow package wiring
 

Hey folks,
Have an 03 silverado that Im having an issue with my tow package wiring. Hooked up my camper to c heck all my lights and the right brake light on the camper wasnt working. After cleaning every ground connection and changing the bulb I found that it was at the truck end. Pulled the connection off my 7 pin trailer plug and tested the right turn / brake pin on the factory harness. Right turn signal works but the right brake does not. Could the factory 7 pin plug need replacing? Does anyone have any ideas as to why this is doing this? or has anyone had this happen as well? I will say that every so often when I go to use the directional to turn left my 4 way hazard lights come on. Not sure if this has anything to do with my issue just thought I would toss that in. Thanks in advance for looking.