HELP! Problem with reverse and interior lights.

[05Yukon]

I have no reverse or interior lights on my 05 Yukon. I got stopped today in the parking lot for not having any reverse lights. This problem must have started today. The reverse and interior lights dont work at all. I have checked the fuses for the reverse lights and tried to find the fuse for the interior lights but was unable too. The one reverse bulb I checked was fine. I dont know what else to check.

 

[05Yukon]

I found out that It is blowing the TBC 2B fuse in the instrument panel fuse box. I tried putting a 20 amp fuse in and it still blew. It blows as soon as the reverse lights try to come on. Does any one know exactly what that is the manual just says truck body controller.