Instrumental cluster Intermittently not working properly

My cluster turns off and on at random. Nothing works not even the diming lights turn on. None of my gauges work, but at random times it turns on. I changed my cluster but did the same thing, then I check the wiring harness that connected to the cluster and check it with the circuit tester some were good, notices one was flickering when I moved the harness.
Point is, I have no idea where to follow it and where it's connect to or even where to buy the whole harness itself.