BMW 20-pin Diagnostic Socket Pin-Out Diagram

Handy pin-out diagram for the pre-OBD 20-pin round diagnostic connector on 80s and 90s BMWs from PinOutGuides.com [https://pinoutguide.com/CarElectronics/car_diag_pinout.shtml] 

 

1       Engine rotation speed [TD]
2       CAN-High     
3       CAN-Low
4       Shielding
7       Oil service and Inspection reset    
11     External starter turn on
12     Battery indicator
14     Battery power     +12V
15     ISO 9141-2 L Line     
16     Ignition +12V     
17     ISO 9141-2 K Line
18     Programming line [PGSP]
19     Ground [GND]     
20     ISO 9141-2 K Line [TXD]

 

https://pinoutguide.com/CarElectronics/car_diag_pinout.shtml

BMW INPA 5.06 for Fxx Series / ENET Cable / Coding etc. - Great Guide + Download!

http://blog.obdii365.com/2017/02/09/set-up-inpa-for-bmw-f-series-coding/

This guy's blog has a great download for a fully working, easy to install / update INPA 5.06 to work with Fxx Series BMWs and ENET to OBD2 cable, so get it while the links are still active!

DOING A FRESH INSTALL:
The guide covers an 'Easy-Install' tool, so if you are doing a new install from the word go, then follow the instructions on obdii365.com and go from there. I haven't tried to confirm it is indeed easy and works, but evidently other people have.

Updating a current version of INPA:

If you already have an older version of INPA up and running, then updating to 5.06 could not be simpler, but it is not quite explained in the obdii365 guide, so follow as below. This assumes you are switching to an OBD-ENET type cable.

1. Locate your INPA and EDIABAS folders; they are in the same place. (C:\...\INPA) (C:\...\EDIABAS)
2. Copy the folder named INPA_Fxx_v.2 from the download into the same location as your existing INPA folder.
3. Rename your original INPA folder if you wish to keep it or delete the folder.
4. Rename the INPA_Fxx_v.2 folder to INPA.
5. Copy the EDIABAS folder from the download into the same location as your existing EDIABAS folder, selecting 'Yes to All' to overwrite any existing files of the same name.

That's it... your INPA will now work with Fxx Series cars. The EDIABAS.ini configuration file is already set for ENET, so just plug it into your OBD port and wait about 30 seconds for a network address to be assigned. Once you get the 'Limited or No Connectivity' message pop-up you can open INPA as normal and should see the Battery and Ignition dots filled.

USING AN OBD-USB K-CAN CABLE:
An OBD-USB K-CAN cable can be used with Fxx-Series cars, but only to read and erase fault-codes. Coding is not possible without an OBD-ENET cable.
To use the update method above and retain settings for OBD cable, make a copy of your original EDIABAS.ini configuration file and merge it into the new EDIABAS/Bin/ folder. Alternatively, re-adjust the settings for OBD after the update, which is the best option if you can be bothered.

Modify BMW USB-OBD Cable for 2005 and Later Cars

If you have an older USB-OBD diagnostic cable that works with BMWs up to 2005 [DIS v44 etc.] then it will need modifying to use with later cars and version of DIS / INPA etc. The process it pretty easy.

1. Remove the four screws from the OBD section of the cable using a crosshead-screwdriver.

2. The case will likely be glued together, so pry it open with a flat-screwdriver and remove the circuit-board.

3. Locate pins 7 and 8 on the back of the OBD-plug itself, which you will find bridged by a blob of solder. [Usually the right-side two pins looking at the face of the board with the LED on.]

4. Use a soldering iron to melt the solder between the two pins so they are no longer linked. [A solder-sucking device is useful here, but it can be pulled off onto the soldering-iron quite easily.]

5. Re-assemble circuit-board in casing and replace screws.

The cable will now work 2005 and later BMW cars, including newer models for all diagnostics using this interface, inc. DIS v55, v57, INPA 6.4.3 etc.

The cable will no longer work with BMWs made before 2005 and DIS v44, so it might be worth getting a spare cable to de-solder. The ideal solution is to solder small wires to each pin that run off to a switch mounted in the edge of the casing. cn555ic has done a very good guide on how to do this on E90post.com - https://www.e90post.com/forums/showthread.php?t=672940.