Brake light problem... Just driver side

Ok, I have a 99 2dr 4wd Blazer, and my driver side brake light only works when it wants to. Parking lights, signals, reverse etc all work fine. Its only the left brake light. Bulbs and wiring were checked and no problems found. I figured it could be the multiple switches in the steering column, and while holding the brake pedal, i pounded on the column. Sure enough the left light flickers on and off. Does anyone know anything about these switches and which one i should look into. Are any special tools needed to get into the column itself?

Also, if this helps, i have an LED tailgate bar on it and the left side of that bar doesnt work either when the brake light decides not to work. Its connected through the trailer wiring, so its not getting power there either.
Thanks everyone!

Try cycling the hazard switch a few times.

I've had that problem after cleaning the dash. The switch can get caught in an in-between position.