1996 Volvo Wiring Help

Hello, Does anyone know where I can get a wiring diagram or a wiring layout on line for a 1996 Volvo WIA64TTES? Interior lights work in the front of the cab, but nothing is getting electrical power in the lower or upper sleeper area. None of the lights work, the fan doesn't work, the fuse/light switch/fan switch panel in the sleeper area is basically dead. I'm just not sure how the wires are routed so don't want to start tearing things apart. All fuses in the main fuse panel under the dash are fine.

Any help will be appreciated. Also, my speedometer soonest work but all other gauges work fine. Any thoughts on that?

Thank you