Armrest Ipod dock

[Swinners]

Hi ya, my RNS510 became faulty so i took it out and put in the RCD 310, i am having problems working the armrest dock, it worked with the 510 if i put my ipod in and pressed CD but its not working with the 310, any ideas? Or is the actual device as i connected my Iphone 4S?!
Also if i take out the armrest centre can i replace it the the MDI dock? Is it the same wire connection underneath? Ta Emma

[bacillus]

You really need to compare the wiring pin inputs/outputs on both units (diagrams on the tops of the units) as its possible that the pin inputs for the ipod dock are different. If they are, it's easy to swap the wires around in the headunit socket.