[Elecraft] K3 cant see the dash paddle

[Robin Critchell]

I have two early K3, 391 and 392.  They both have been back to have the 
connectors/ribbon cables updated many years ago

392 recently stopped sending dashes.  If I switch the menu setting from 
dot tip to dash tip it generates dashes just fine (but no dits)

I measured continuity from the paddle through to the tip and ring solder 
points on the board where the jack solders down

The Tip line measures 5 volts open and solid low when tip pressed on the 
paddle

the sleeve side looks like its floating around zero and goes hard low 
when dash is pressed, but the radio doesn't see it.

Measured at the solder points on the board where the jack solders down 
so its not the jack or the paddle or the plug and cable

Radio sends straight key just fine

Some "laying on of hands" to shake the connections didn't help, and 
Gently flexing the board where the jack is attached did not have any effect.

Next step for me is to have time to drag out the schematic and take the 
radio apart and trace the path

I am hoping somebody else has had a similar problem and can save me some 
troubleshooting tracing time

Thanks

Robin, WA6CDR
Radios (and I) went to VP6DX so the radios are well experienced