I have a 5050 that has a blank panel. Machine works but you can`t see the panel. I have removed and reset all panel boards and dimms. I gave them a loaner panel off another machine to get them going and it works great.I also have another 5050 that the customer says it goes off and on from time to time or dimms out. Could the backlight be going out on these panels? Well the one that is totally black must be bad?

Had cold solder joint on Power Supply PCB causing similar problem. I believe it was connector YC1. I wiggled the connector and display would go on and off.

have you tryed the ribbon cable, and there is a bullitain out for that.

Thanks i will try that.

Check and see if you have an LCD inverter pcb that has gone bad. That would be my guess.