My driver side brake light and side marker light don't work. I replaced the brake light bulb and nothing. Are the side marker and brake light on the same circuit? No blown fuses.

 

Fixed it, they do share the same circuit. Changed the side marker bulb, brake light works now.

 

I had the opposite issue, always popping the fuse when the brake pedal was pressed. And yep, it killed both! On mine though, the issue was kind of funny to find. Turned out the bulb failed, but one of the arms that hold the element in the bulb bent over to touch the other one so it was enough metal to not burn through and was shorting, killing the fuse. Did not expect that one! Started tracing the circuit from the fuse panel back and found that when the bulb was pulled the short went away

 

Plot thickens, side marker works but driver side brake light doesn't

 

I have narrowed it down to a bad socket. The wire and connector are getting power but not the socket where the light goes.