[Elecraft] KAT3 not responding to ATU Tune button

[Bill Phillips]

Has anyone experienced this? After years of faithful service the ATU Tune
button on my K3/100 has stopped responding. I can switch between antennas 1
and 2, step through the Ls and Cs, and bypass the ATU, all in the
configuration menu but not with the front panel button. I tried a  reset but
no joy. I'd be grateful for any suggestions for further diagnostics, of
better still, a cure. Thanks

Bill   AD6JV