.lacrosse wiring

I picked up a LaCrosse CCB-90-9 and the wiring is brittle. I need a wiring harness or can I rewire this myself? The wiring harness is very unusual looking. Several wires connect to a round black disk that looks like a small hockey puck. It's made of rubber and the connections can't be viewed unless I rip into this thing. Any help is greatly appreciated.  

Dwight

Dwight.
 Several different manufactures used this type of wiring harness. The "puck" is just a sealed junction box . I usually have to rewire with a modified harness from another box or carefully draw up a wiring diagram of the existing wires and rewire....................Jack
  The junction box is usually the compressor/ thermostat, and fan (s) connection to the power cord. It gets more complicated if there are light-ups and relays and such.