[Collins] KWM-2 Tune and lock positions not functioning.

[Cam and Juli Hedrick]

Hi all, before I dig in to see what the problem is, I thought I'd ask and
see if anyone has experienced this.  The rig works fine in LSB, USB, and CW.
When I tried to tune it just a bit ago I got no output in the tune and lock
position even though I had plate voltage indicated on the meter.  Any ideas
as to where to begin trouble shooting?
TIA
Cam
WA4JKW