Tractor Repair: JD diesel electrical problem, wire colors, dash lights

Question
My Deere 790 with about 220 hours on it suddenly went dead on me. It had started up normally, I got it into position for a job, tried to restart it and I didn't leave the starter engaged long enough for the engine to catch. I turned the key quickly again, and nothing happened. Even the dash lights didn't illuminate. I found an animal nest under the seat, and cleaned it out. There did not appear to be any damage to the wires or to the safety switch under the seat. I took off the panel below the dash and checked the ignition switch with a voltmeter. As far as I could tell, it works properly. In other words, I got circuit continuity between two leads when the key was in "on" position, and between two other leads with the key in "start." Under the hood, there was one spot close to the fuel tank on the right where cable conduit was chewed and one of the two wires showed bare copper. Someone suggested the neutral start switch could have failed, but it seems to me that if so, the result would just be that the starter wouldn't engage, not that the panel lights would be dark. Any ideas?

Answer
Hello,

  Yes, if the problem was a neutral switch or some other safety switch, the dash would power up and it just wouldn't turn over.   Check the battery cable connections and the condition of the battery first.  Check all fuses.  If OK, then use your voltmeter to check the voltage from the starter connections going up to feed the instrument panel.  It could be a bad connection right at the starter, or somewhere in the wiring harness to the dash.  I have no access to a wiring diagram, so I can't help with wire colors, etc.