[Elecraft] voltage display problem

[MARY HAYS CARNEY]

I have some problems with my K2 transmitter section, but first would like to clear up a problem with the voltage display.  After giving the correct value for several days, it suddenly began to read 23.3 volts no matter the input voltage.  This persists even after resetting both the relays and the whole system (4-5-6).  The volltage at the Vsense of U6 (control brd) is correct; I.e. about 2.1 volts for 11.9 in or 0 for 0v in but the display only reads 23.3 v.  The current display is correct. Any hints of where to look next?

joe carney KB3FBR