MCX-1000 No function

[DrDave]

We are an authorized Yamaha servicer and not all that often see the MCX-1000
A customer came in with one this week and claimed it was hit by lightning.
We are trying to determine if this a natural failure or lightning.
We can get it to power up,but no functions.The client status lights strobe one by one then the Timer ,LAN standby,and encoder lights come on then all go off except LAN standby.The display shows LAN standby mode Setting now...and then the display will turn off ,the green LED will return to red on the power button.The unit can also be put into one of the test modes that allows you to test display and fan etc. everybody so far has said replace the main pcb.Cost is $455 .We want to be sure. Power supplies all check ok and no error codes. Anybody have any thoughts? Thanks in advance.