Symphony head unit, what do the wires do

[Alex JB]

This is the sticker on the symphony CD/tape deck unit


So I realised that the canbus switches the unit on so I found an ignition switched +VE to turn on the aftermarket unit.

I don’t have steer wheel buttons and the only other thing worth getting off the canbus is the illumination signal (lights on) and reversing signal, both can be had from elsware.

There is however the’K’, ‘alarm gnd’ and ‘bose’ lines in the plug of the harness.
What do these do?



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[rollerton]

I know in the similar year VW's (which have basically identical hardware for the stereo) the Alarm gnd is actually part of the ground for the alarm. If the stereo housing wasn't seated right in the dash your alarm wouldn't work right. I don't think it has that effect on the C5, so maybe it doesn't do much.
K-line is the part of the comm link (like the can bus) for the stereo. I think (?) Bose should be the common ground wire for the subwoofer if you have Bose.
Those 3 wires are basically ignored for aftermarket stereos.

[Alex JB]

Interesting, thanks.

I think I might try grounding the Bose wire, I have the 5 channel Bose system and I am getting alternator whine.

I see the CAN HI and CAN LO on another plug, I assumed most of the car info given to the radio is on that. But the K line I don’t get, maybe it’s the radio station info to the DIS?


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