Hello everyone, well as many of you may know by now BMW has discontinued the Z4 navigation retrofit wire loom, so if you want to retrofit a Navigation system you either have to get the loom from the guy your buying the system from or buy the BMW X3 navigation retrofit wire loom.
this will just show which wires to connect and where and which ones you need to make it work.
all original instructions will work except where the X3 harness has different connectors as the Z4 harness.
first, if you plan on doing a nav retrofit in the future i suggest buying the X3 loom ASAP as their are only around 25 or so left in the world and their gone forever.
the part number you will need is
-X3 navigation retrofit wire loom- part # 61120390114
First off the X3 harness has two black connectors, these black connectors will fit nothing on the Z4 so you will have to remove them and you will have this assortment of wires.
i cut all the connections off and got rid of what i didn't need. you don't remove any wires other than the ones that where originally held within the black connectors, i just removed the factory connectors and looped the wires back and taped around them so no cutting of actual wire was needed.
i cut what i didn't need and wrapped them away showing only the wires that i needed to splice into the Z4 system.
then its business as usual, route the system as the original instructions show you until you get to the stereo Ibus connector, this is where you will need to splice into the factory loom. find a good spot on the stereo loom by the Ibus and find the correct color wires, cut them and then connect each end to the retrofit loom like in the image, wrap up and your done with the splice.
in the pic below i striped the OEM tape back to reveal more wire, got some slack and then spliced, you can see the stereo Ibus in the bottom of the PIC, taped it back up and then wired up the rest of the system per the PDF
Z4 navigation retrofit instructions, you just have to change where you splice into the system, with the X3 harness you no longer have to splice in the middle of the car, you now have to splice at the stereo Ibus connector.
not to hard once you know where and which colors you need.
their is a lot of info on the retrofit from other forums but none had pics of the loom with which color wires go where.
hope this sheds a little light on where to splice, its simple enough and the system works great!