Cannot select CD changer input on Head Unit?

[kPATm]

Well I went ahead and bought this

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWNX:IT

I have it conected to the Ipod but I cant change my HU to play from the CD changer.Here's my Head unit

https://sl-i.net/FORUM/

I take it the CHR button on the right is for the CD changer

How do I change the source to the CD changer input??

[jey]

I wonder if there is some sort of data connector to the CD changer to control it - just plugging the iPod into the audio input may not be enough for it to recognize the presence of that source.