Upgrade NavJ to Mk3/Mk4

Upgrading a Japanese navigation system to a Mk3 or Mk4 required some wiring changes and new plugs.  With a little skill and enthusiasm you can make this migration yourself.

The black NavJ computer plugs need to be replaced with the ones shown here.

Refer to the detailed instructions prepared by Jochen Siegenthaler here.

The 18p connectors are available from BMW - refer to the website, see this page here:

You need item #9 (18-pin connector), x 2 connectors

  • 2 x pieces Part 61138364666
    Plus you need some pins, about 4 will do, because most wires can be removed from the Jap plug and inserted in the Euro plug:
  • 4 x 61130005197
    You will see some wires (power, ground) have to have new pins fitted.

Remember: you also need to join the FM antenna (it loops through the Jap nav, it is used for VICS reception in Japan) once you disconnect the Japanese nav, otherwise you have no more radio reception, (or reduced radio reception). I used a custom-made SMB-SMB coax cable, 100mm long

Also, the Jap GPS antenna connector (type: Fakra) will not fit the Mk4 because it does not have the right locking mechanism. I used another SMB-SMB extension lead, also 100mm long, and used tape on the Fakra-to-SMB connection to secure against vibration.

1. 61138364666  $0.68 - 18 POL. Universal socket housing uncoded
2. 61130005197  $1.65 - BUSHING CONTACT 0.2-0.5mm
3. 61131383650  $0.55 - Lock
4. 61138364662  $2.30 - 18 POL. Covering cap