Nord stage 3 power pcb

Hi folks, my Nord Stage 3 88 decided not to power on recently. No reason. It intermittently would not power on for the last year or so. But now it refuses totally. It’s out of warranty.
Things I tried:
Unplug everything, power on holding store & shift
New power cable
Several power outlets
Opened up and checked all ribbon connectors for corrosion and reseated
Checked power pcb and main board pcb for obvious damage
Checked all the fuses on power board and fuses f1 to f6 on main board for continuity
When plugged in and switched on there are no displays or lights and no USB connection can be seen if plugged into computer host. The power unit is warm so I believe the main transformer is getting supply.
I’m looking first to replace the main power board to see if that is the issue. Looking for supplier and price.

I’d like to test the output voltages from the power supply board however I don’t know what the pin out is for the 12 pin power ribbon cable? And I can’t find a circuit diagram.

Any thoughts?

Ok so update on this. The main power board is outputting a steady -12V +12V and 5V. So it doesn’t look like it’s a power board issue. The main board is receiving +12V and -12V . I’m going to check the 5V supply on the main board.

There is a blue 3 pin output on the main board, it’s unmarked on the outside of the chassis, so I assume it’s diagnostics?

Any help on tracing this dead synth would be appreciated.

Tuejan

So looks like the Main board has power but is just not booting. No relay clicks when switching the system on, no USB discoverable in a host pc. I’ve gotten in touch with JAM in Canada to see about a replacement Main Board.