[Elecraft] K3 Power Out

[Glenn Haffly]

I have K3 serial number 2802 with the 100 watt option. All was well until 
today.
Currently there is zero to minimal output.
Rotating the power knob to 12 watts you hear the relay. Regardless of power 
setting
only 1 bar on the RF is lit.The fans are workings.
Rechecking the TX calibration it failed at 5 watts with the ERR TXG message 
on the display.

Where do I start?
Glenn , K5ZE