So my passenger side tail light is not working correctly. I've changed the wiring harness and checked all the bulbs and fuses. The turn signal and brake light work but not the actual tail light. All the bulbs are new, wiring harness is new and the drivers side works like it is supposed to. I'm out of ideas except for buying a whole new taillight which I would prefer not to do. Any help would be highly appreciated

You can find the wiring diagram for your taillights here starting on EXL-63:
https://www.nicoclub.com/service-manual ... %2FEXL.pdf

The connector pinout is on EXL-69. First thing to do is see if the license lamps are out. If so, you know it's a wiring or fuse issue because the righthand tail and the license lamps are on the same circuit and fuse. The lefthand tail is on a different circuit and fuse. Dunno how you've checked the fuses, but they're both in the IPDM under the hood (not the cabin fusebox) and a test lamp is the only right way to check them. Visual checks are worthless, they tell you nothing about whether the fuse has power or whether the circuit can carry current. If the license lamps are out then you know the problem is fuse or wiring, if they're lit then you know the problem is limited to the righthand lamp or wiring. Post back and I'll assist further based on what you find.

The license plate lights are out as well. When I checked The fuses I did use a circuit tester, however I only tested the passenger fuse panel and fuse box #2 as it's referred to in anything I've read.

The fuses for the taillights are in the IPDM, it's upside down at the rear of the fuse & relay box located forward of the left strut tower.

VStar650CL, thank you for your help and wisdom. I found the blown fuse in the IPDM and changed it. I'm happy to report that my taillight is working the way it's supposed to.