[Elecraft] USB not working

[Vasan Chakravarthy]

Hi all,
I completed assembling my K3 kit (Sl#3191), and it was a pleasure!
The rig is working fine.
However, I have one big problem.
It does not transmit on USB, but LSB is fine.
i.e., I made some contacts on 7MHz, but nothing works on higher bands. I see
no power at all on 14MHz (USB) .
The meter in SWR/PWR, has no indication when use the Mic. No power is going
out.
Everything works fine on 7MHz (LSB).

Hope one of you can help me troubleshoot this.
Thanks in advance,

Vasan
wz3h