BMW E90 320i Help With OBD II Port

Hello there 👋 

I have a 2008 E90 320i From Japan and am having some issues with the OBD II Port. I’ve noticed when I try to scan, the scanner sometimes establishes a connection and then while scanning for codes it just goes blank like it lost power. I’ve tried multiple scanners (BlueDriver, OBD Link CX for BimmerCode & Carly) and none can make it to the end of the canning process. So I got to digging and pulled the OBD II port to check pins and wires.

Also found a pinout online for E90’s to make sure it was pinned correctly.

I believe the pinout I found was: 

Pin   Signal                                Description

1       +12V                                   Ignition (In run Or Start)

4       CGND                                Chassis Ground

5       SGND                                Signal Ground

6      CAN HI                              CAN High, J-2284

7       ISO 9141-2 K-LINE       Engine (ISO-9141 and ISO-14230), Automatic Transmission Diagnostic (In Some Models)

8      ISO 9141-2 K-LINE        IKE/KOMBI, ABS, ABS/ASR, ABS/ABD, ESP, DSC, Airbag And Other Electronic Equipment

9      TD/RPM                            Engine Rotation Speed

14     CAN LO                            CAN Low, J-2284

15      ISO 9141-2 L-LINE       L-Line Of ISO 9141-2 And ISO 14230-4

16     +12v                                   Battery Power

So I pulled my OBD II Port and I found that pins 1, 8 and 15 are not present. I also found this rectangular box with some type of capacitor in it attached to the harness with the two can bus wires going through it.

I also have two parts cars from Japan with slight variations in spec, totalling 3 E90’s that I have:

                 Year        Production Date      Engine Code    Transmission    Spec

Main -    2008      10/2007                       N46B20B          GM                        Cloth Electric Seats Non Heated

Parts -   2008       08/2007                     N46B20              ZF                          Leather Electric Seats Heated

Parts -   2010        12/2009                      N46B20B           GM                        Cloth Manual Seats Non Heated

So I pulled the OBD II ports on those as well to check if they were the same, and oddly enough the other 2008 model was setup differently but the 2010 model was setup the same as my white 2008 model. Maybe the transmission used plays a roll on the OBD II pinout seeing that my white 2008 model and the 2010 model both use the GM trans? The 2008 parts car doesn’t have the box with the capacitor in it.

Below I’ll show you the pinout for each vehicle:

White 2008 w/GM Transmission:

Silver 2008 w/ZF Transmission:

Dark Blue 2010 w/GM Transmission:

Any idea what I need to do to get the port to work? I’d imagine I need to start with adding a +12 Volt signal from the ignition switch.

Edited July 23, 20251 yr by TinoTheGreek
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