brake light issue
 

im new to this part of the neighborhood. Im usually around the 67-72 section but i just bought a nice 2000 gmc sonoma and my uncle has a 2001 s-10 4wd and both are having the same brake light issue,
the driver side brake light is inop. the turn signals work just fine but no left brake lamp. even the trailer plug left brake lights are inop. is this a comon issue?
ive searched for broken wires but nothing on either one.