I'm hoping someone might be able to hep with this...
First of all, I have the factory Infinity sound system in the XJ, with the standard amp, head unit and speakers, the factory Alpine CD changer under the back seat, as well as an Infinity Basslink subwoofer that I spliced into the speaker wiring myself.
I bought a different head unit as I thought it looked slightly nicer. I'm pretty sure the new one is the same one as is found in the XJ Classics over here, but this particular one came out of a Voyager.
When I took the old head unit out, I found a strange box (very roughly 3x2x2") on the CD changer wire. The wire comes from the CD changer, which plugs into the box with a standard round 8-pin plug. There is a rectangular 8-pin plug on the other end of the box, which has a wire coming off it that goes back into the standard round plug again, which is plugged into the head unit.
I took the box out and plugged the changer straight into the old head unit, and the CD changer stopped working.
With the new head unit, the CD changer doesn't work with or without the box plugged in. The changer simply sounds like it's repeatedly turning on then off again.
So, there are two questions really - what is this box, and is my new head unit simply incompatible with the CD changer?
If it helps, my old head unit is the top one, and the new one on the bottom:
[attachment=1]
Secondly, I also found this plug behind the radio, which wasn't plugged into anything. What is it??
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