[Elecraft] K3 Goes to TX on Turn ON

[paul ecker via Elecraft]

Have a problem that just cropped up last night. When I turn on my K3, the red TX light immediately goes on. After connecting and disconnecting all external connections to K3, I determined the culprit was the RS-232 cable to the P3. If I disconnect the cable problem goes away, red TX light goes out. I tried swapping  RS-232 cables but same problem exists. Any ideas where to look on this ?? The P3 and K3 have been co-existing fine til last night.

Tnx & 73 Paul
kc2nyu