Total lockup vr-5000

I just bought a VR-5000 used from another ham. He told me it ran fine on its own PA-28 Power Supply but he used a larger regulated supply. He tells me he had it about 5 years. After being shipped half way across the country I received it fromUPS, and set it up with the PA-28. It ran fine for 4 hours while I started to learn how to drive. After 4 hours I noted the supply was very warm so shut it down. When I tried to turn it on later I got the Error Low Voltage message and lockup.  I have tried everything. A 20amp regulated  supply, factory reset on start up , disconnected the powetr cord for hours. The only thiing I can get is the firmware message Ver V 1u. 17.
 I just signed on to this group today. No idea what to do except take a $400 hit . ANy help??
 John
 VE4ZP