99 PreRunner tail light help

Hi folks,
I am brand new to this site. But I have been reading the forums for a long time. Recently, I noticed my left tail light is out. Fuses seem to be OK. At first, none of the brake lights were coming on, and the reverse lights were not coming on either. However, today the brake lights and reverse lights are coming on on the right side only. Does it seem like just a bad bulb? Thanks for the help.
~Nick

 

might be a trailer light harness module, when they go bad lots of weird things happen with the tail lights. disconnect it and see if that fixes it, if it does try this fix: http://www.tacomaworld.com/forum/lighting/347862-diy-easy-10-trailer-lights-plugin-fix.html