Amazon.com: Add A Bass Subwoofer Amplifier Adapter Interface w/Amp Remote Wire to Factory OEM Car Stereo Radio for select VW Made for Jetta Golf CC Passat EOS Tiguan etc- Vehicles listed below :
VW Dynaudio amp signal issues - solved | DIYMobileAudio.com Car Stereo Forum
Installation Audio System m165 evo2 in VW passat b6 - YouTube
Volkswagen Passat B6 - how to connect the amplifier and subwoofer to the factory
Boss BASS600 - Stealth Variant Subwoofer Install | Volkswagen Passat Forum