How to DIY D+KCAN cable with switch pin 7 & 8 for old & new BMW cars

I modified my D-can cable and installed a switch in order to have it operational with 2006 and earlier models that use the OBDII port. My cable did not come with an adapter… 2/2007 and older vehicles requires the pin 7 and 8 to be bridged to work..3/2007 and later requires pin 7 and 8 to be separate. So for 2 bucks at Radio Shack and about 20 minutes of my time, I have a fully functional cable for both applications!



modify-dcan-cable-pin7-8-1 modify-dcan-cable-pin7-8-2


I will post up pics and give you the DIY when I get a chance..Its actually very simple that any average person can do that has access to a drill and a soldering gun.

Tools needed..
1Small philip screwdriver to take the D-can cover off
2Radio Shack micro on/off switch (can be two prongs or three) and some wire 24 guage.
3Soldering gun
4Some type of glue gun or glue adhesive
5Drill bit 5/16 to make hole in the D-can cover

Locate pin 8 which will have a number on the side of the board. One side will have the digit 1 and the other digit 8

Once you locate pin 8, thats the pin we will be using as well as the next one over. Connect each pin 7 and 8 with a separate wire and then use the soldering gun and connect each wire to the micro on/off switch… If you bought a 2 prong on/off switch connect it to each side, but if you bought a switch with three prongs, connect the middle and one of the ends, doesnt matter which one. At the end there will be one prong end not used…Neatly place the wires snug so that the D-can cover can be closed without anything preventing it to make a closed seal and your done. Screw in the 4 philip head screws in their respected holes. Note which postion is on and which is off by some type of label on the outside of the cover…SImple! Note on my first pic, I have a switch with 3 prongs, but I snipped off the 3rd one just to make it easier to solder…



Note: it’s your own risk. if you are not experienced, you’re advised to a decent INPA cable:

bmw-inpa-cable-7-8-pin bmw-inpa-cable-pcb-1 bmw-inpa-cable-pcb-2


This K+Dcan cable comes with a switch pin 7 & 8 and FT232RQ chip


on DCAN cars one pin is used for a ethernet connection and the other to the K data line – on K line cars, both pins are connected to K data lines and that creating a switch mode circuit would cost more than the interface is worth. The 2 most sensible options are both hardware-related:-

1.Use an adapter (such as the one sold by One Stop electronics) which internally bridges pins 7 & 8 or…

2.Mount a small switch on the OBD plug end of your adapter, which can bridge (for K line) or separate (for DCAN) the connection between pins 7 & 8.