2003 Chevy Tahoe tow lights and power window

this is a 2 part question. my trailers lights stooped working and i've checked the fuse box on the side facing the driver door and inside the engine compartment & can't find any blowns fuses I followed the wiring harness to the floor under the emergency brake lever to a box but I can't take it apart,is that where my prblem is and also my passenger door window stopped working and I tested the cables on the door and window module and there's no juice at that end aside from this the vehicle is falling apart poor GM manufacturing but that's a whole different story