Disklavier

I own a Disklavier DC2A with the DKC55RCD control unit.   The piano is almost 
3 years old.  Last week the piano went entirely dead while it was playing.  I 
removed the CD/Floppy control unit from the piano and took it to the local 
Yamaha dealer.  I hooked up the unit to a known working piano and it worked just 
fine.  I believe that isolates my problem to the amplifier itself.  Yesterday 
the technician (a piano tuner by trade) came to my home.  After laying under 
the piano for a few minutes with a $30 Radio Shack VOM, he surfaced and said 
that the power supply was bad. I offered my phone and my FedEx overnight 
priority account number to enable him to get some parts coming.  He declined.  He 
wasn't sure if Yamaha was going to send an entire amp or just a circuit board.  
I encouraged him to call to find out.  He advised that he didn't have enough 
information to make a call.  He needed other information that he did not have 
with him.  That irritated me as I had given him the above mentioned explicit 
information at the time I set up the service call.  I had checked all of the 
connections as he had directed over the phone... to avoid a nuisance service call 
for some easy to fix reason.  Here are more specific symptoms that the piano 
exhibits:  When the on-off button is depressed, absolutely no lights 
illuminate or disk operation occurs.  A tiny relay does click in and out within the amp 
itself when the on/off switch is depressed.
 
Yes, it's probably a power supply or related circuitry.
 
Does Yamaha typically replace boards or do they swap the entire amplifier 
unit?  Do they have an exchange program or does the suspected item have to be 
returned to Yamaha for repair?  What is the tech support number at Yamaha?
 
I'm a former TV repair technician, yet I purposely left the piano repair up 
to a "qualified" technician as it is still under warranty... but if this is a 
simple board or amp swap, I'll gladly do it myself.  By his own admission, the 
repair person is not at all familiar with the removal/repair of the amplifier 
unit.
 
I'd appreciate any help from this group.  I believe that an infusion of 
additional knowledge will enable me to move this repair ahead to a successful 
conclusion.
 
Thanks.....Merry Christmas