Thanks KiwiJochen,

Finally someone who understands exactly what I am trying to attempt !!

I have the instructions you mention but thanks for the offer.

I understand the RGB cabling you mention, I just had visions of heavy 75 ohm coax running through the vehicle and attempting to home it into a connector with great difficulty.

**Update- Having studied the circuit diagram on page 15 of the retrofit guide I figure the following:

The violet connector on the nav computer connects to the black/white cable of PIN 8 of plug X11175 on the instrument cluster. This connector also carrys the reversing signal? There is another cable on this violet plug described as X229- Terminal R connector, I don't know what this is for !!?

So I need not use the violet connector on the new retrofit harness, I can simply leave the original harness in place and use this in part alongside my new retrofit?



I can strip the speakers, aerial, cd connection from the retro fit harness (Item A1, A2, A3, A4, A7 and A9) to make thing a little neater or else find a harness with just Item A5 and A6 on one end !! I get the feeling I'll be getting a retro fit harness and stripping it back, wasteful as it may seem, I fear it will be my only option. A Breaker isn't really an option as specs are pretty low on BMWs round these parts!! Not much need for navigation round here !!

The rest should be almost plug and play from what I can figure !

The white plug (X18802) at the monitor end, will connect to the nav computer via the blue socket (X1313) (You mention in a previous post that the blue connection on the nav computer goes to the blue plug on the display, from what I figure, the white goes to blue !! Am I wrong??).

The blue plug (X18802) at the monitor end, will connect to the radio module via X13649 or Radio IV.

The black connector on the radio tuner (X18126) will stay as is.

Forgive me for asking this as I should have checked whilst I was digging around earlier, how does the cd changer (Also located in the rear) connect ? Is it on a seperate plug or do I need to add it to a connector? There are two wires running from the cd player connector (X13321) that cross into the radio module (X13649). There is also a cable (X13321) that connects from the cd changer to the radio module??

And finally, the aerial stays connected to the radio module whilst the GPS coax that is currently going to the GPS module will connect the the GPS socket on the new MK4 computer.

The earth connection (X3279) will join the earth strap along with the existing harness?

The only other thing confusing me (As if theres not enough already !) is X3279, X1543 and X18344 which appear to go nowhere !

Am I there??

Thanks again and again