Connection between display and power bar board lost

[Rob F]

You changed something, those voltages look better, however you shouldn't have any voltage on pin 4 unless the boards are connected, if you have nothing connected only voltage on the 3 pins. What kind of patch cable are you using? I've used one that came with a router and it was garbage, you need a real cable. It should be working with those kind of voltages if nothing was ruined.