[Elecraft] K3 shuts off

[Mike]

I was at a friends today, looking at his K3. It's in the 1000 range of 
serial numbers, not a kit.

If power is set above 95-96 watts, the rig shuts down instantly when you 
transmit (at least in CW and if you press the TUNE button. Didn't try it 
on any other modes).

His power supply reads 14.6V, it's a 20A supply, but we didn't read it 
under load. Does the K3 have the ability to display voltage and current 
draw?

I downloaded and installed 3.68 firmware, but the problem was there before.

Clues and hints, please?

73, Mike NF4L