Car Stereos: aftermarket deck with factory bose amp, vw jetta glx, vw jetta

Question
hi, I have a 98 vw jetta glx and just bought an aftermarket deck. I got the wiring harness and there is power going to the deck but no sound from the speakers. I've been told it's something to do with my factory bose amp. How do I get the deck to work?

Answer
Hi Moe,

If you still have the original Volkswagen head unit available, you might want to look at it for wiring clues.  Most VW radios have a pin-out diagram available on top of the radio chassis.

Chances are there's an amp turn-on wire that needs to be activated, and you might have to make connections to signal wiring.  Unlike the VW Monsoon systems, a Bose package in a Volkswagen or Audi usually uses a low-level signal between the head unit and the Bose amplifier.  The signal wires are often found in the third row of plugs (yellow, green and blue) which aren't connected with the standard Volkswagen wire harness.  You might find separate (+) signal wires for left and right, front and rear, as well as either one or two "common" negative wires.  Usually, the easiest way to make this setup work with an after-market radio is to splice RCA cables into the low-level signal wires, and plug them into the head unit's RCA outputs.  The amplifier turn-on wire needs to be connected to your head unit's blue/white remote output lead.

Again, if you have the original radio with a pin-out diagram available, it will make it much easier to figure out the wiring.

Hope this helps!

Brian