Dash and transmission problem. Electrical or Ignition Switch problem? Please help !

I start my 2000 Z71 the dash gauges and shift indicator stop working. At the same time my tranny seems to be stuck in one gear and wont upshift or downshift. Then the service engine soon light comes on. The problem is intermittent because sometimes shutting down and restarting fixes the problem, but not all the time. I can go days or weeks without having any trouble then all of a sudden it starts doing it again. Checked all the fuses and checked battery cable all is fine. Could this be the ignition switch?

I have a freind that has a late 90`s chevy pick up that would not shift into high gear occassionally. He took it to trany shop and ignition switch is what they traced it back to be . So you could be on the right track with your thinking

If the service engine light is on, find out what code(s) are stored. The voltage at the transmission harness should also be checked. If it is not the same as battery voltage, then the ignition switch could be the issue.

//2000CAYukon