Connecting AUX cable- Need clarity

[TerminatorX5]

Originally Posted by mcfee03

Ok so could you tell me how to find out what radio I actually have? And what option do I have for changing the firmware (and do I need to in order to use an AUX?)

Ta.

I can see that you have a picture of a 3 pin connector, which is for the cars that have a boardmonitor (with or without Nav), and there is a 3-pin mating connector hidden behind the monitor.

Yours does not have a monitor, so all the connections would be made at the radio itself. I do not know about the radio firmwares and various versions, but assuming that your radio can handle the AUX, you would remove the pins from the 3-pin connector on the cable, and insert the free-hanging pins into the existing connector housing.

Your colors are not factory colors - the factory always uses brown (or variations of brown/other color) for ground, as per German DIN standard.

The Radio determines that the AUX cable has been attached by sensing a 300 kOhm resistance between the Left and the Right channels.

there are only so many combinations for the 3 wires that you have - basically only 3 - the ground wire can be in position 1, 2 or 3. The other two wires, even if mixed up, still would work, either with correct left/right channel, or reversed, right/left channel.

I would suspect that whoever built this cable (from the picture that I saw in this thread), might have used the regular left/right coloring from the RCA cables...

the metal parts of the wires must not touch each other, as they will be shorting the signals.

What is the manufacture date of your radio? from the picture it looks like model CD53, made in May of 2002... in that case, your radio simply might not even have the AUX option... But I don't know enough about the radio variations to be conclusive...