[Kenwood] TS 870 Error Code

[spawnn]

TS 870 displays error code "EE"
can anyone define this error code ?
Problem  USB/LSB modes nornal
CW mode no receiver rf signal received  audio very low

Transmit normal power output
HS0ZAA Bangkok Thailand

response to question CW speed setting
Manual page   6
Press Channel 1 and 2  together
keyer sends F
with keyer send  S 25
end