Have used 2011 jetta MK6 tdi sportswagon.
Original radio (satellite/no gps) was replaced with RCD340. Very bad reception.
Disconnected antenna (3C0 035 507 C) and reception went to bad from very bad.
Replaced antenna with Monsoon antenna. No change. Bad.
Could be bad radio or bad booster (if present).

Where would the booster be? Think it would be a 1K9 035 552
Suspect installer didn't connect power to booster.
If booster exists, where might I get the connector pin out description?

Thanks.