I pulled my radio out of my 2004 last night. Just to try out my removal tools. On the back only one multi pin plug was in the back of the radio. The other multipin socket had nothing plugged into it. What is the other male plug on the back of the radio right on top of the one with the wires plugged into it for? What other plug would go into the back of the radio? The empty socket is the same size as the one that has the one plug in it.

 

possibly for the NAV unit... wonder where the GPS receiver is on these things when equipped with NAV.

 

The other plug contains auxiliary inputs for hands-free phone kits. I'm not sure what else. The folks at Becker might be able to tell you.

 

I've got my radio in bits at the moment trying to suss this out. I am looking for a way to tap a AUX in to the pre-amp for an iPod. I know I can tap straight in to the amp, but I wanted to control the source and volume from the head unit. Anyway, here's a pic of the Becker connector on the rear. I have not cross checked this against the Crossfire manual yet though, so they may be different.

 

From your diagram there is a plug for a CD changer. Does this mean we could remotely mount a 6 disc? Where can this be bought? Why wasn't this a factory option?

 

It has been discussed at length before and it seems to be generally accepted that the Crossfire version of the Becker unit does not support a CD changer. Some time ago I checked with a local audio specialist who referred it to their supplier of CD interface units and the answer was that they could/would not be making a module for the Crossfire. Looking at the PCB on my radio it would appear that all the connections are actually present and connected to the PCB, so it may be just that the Crossfire firmware version disables the feature. I'm still poking about to see what I can find out.