See below for link to manual. Table on LED signals indicates flashing green means:
"Receiving signals but ID is unmatched."
Sounds like your receiver is not yet linked to your new transmitter.
I will be interested to see how this works out because I have the same transmitter new in box to be setup this weekend. I have a different receiver though (r6208sb).
I think the problem relates to the newest FASSTest receivers, like the one that come with the 14sg transmitters. The older model receivers 6203, 6208 are not latest gen. Need to be sure the receiver is in 'Normal' mode, not 'High Speed' mode. The newest receivers are high speed only I think.
Here's another thing to keep in mind:
"Originally Posted by wraptor
Hoping to get some help here cause I'm at a loss. Trying to install Futaba 8FG/R6208. Removed the old receiver and plugged the s-bus into the R6208. Powered up my TX then the Phantom. Solid green light on the Rx but the Phantom goes through it's normal boot up then I get yellow light flashing quickly which means it lost TX signal correct? Not sure what to do to fix this. *FIXED* Forgot to change to D-Bus in the Naza Assistant."