Hi GGVSL,
Sorry, I must have missed this thread earlier.
I wrote the original text for connecting 'Flarm In' to PilotAware via an FTDI RS232 Serial to USB cable, which is now on the Pilotaware website and have also been instrumental in connecting 'the other way' to provide GPS Data from PilotAware to transponders for a number of users to provide Mode S-ES ADSB Out.
Assuming you are using the recommended FTDI cable for your application (which sounds likely), the correct connectivity for ADSB-Out is 'Orange' - 'Data Out' wire to Pin 5 'GPS Input' of the Transponder Multi-pin connector and the 'Black' - 'Ground' wire to Pin 4. The LED should flash RED to indicate that Data is being transmitted from the PAW to the Transponder. (It flashes GREEN to indicate that data is being supplied to the PAW by an external source such as a Flarm Receiver using the Yellow and Black wires in the FTDI cable - which you don't use for ADSB-Out).
As your system was presumably running properly in the past - and assuming nothing has been changed physically or in the PAW setup - the most likely reason for the dropout would be a loss of GPS position reports, though there could be several reasons for this happening. A quick check would be to make sure the FTDI cable is in the correct USB Port and that both that Port and the Transponder are set to the same Baud Rate (9,600 Baud Recommended). I can talk you through this if needed.
A screenshot of your PAW Configure screen ( as requested by Lee) and also your Home Screen would help us to check what is going on, though if the GPS loss was temporary or intermittent, the reason might be difficult to identify. More extensive checks would require access to the PilotAware track log for the flight in question.
Hope this helps
Regards
Peter