Wiring an M52/S52 interior OBDII port

[Northern]

How to wire a glovebox OBD2 port on an E30 + M52/S52 harness.


For reference:
X19527 is the E36 OBD2 port.
X6000 is the DME connector.
X6002 is the underhood 20pin ADS connector.
X6031 is the smaller connector next to X20 and X69 on a stock OBD2 M52/S52 harness.

PG 87 in the ETM shows pinout of X6002+picture of X19527 and which pins are jumpered by their caps. Note you cannot flash the ECU with this method unless you also bridge pins 14 and 18 at X6002 in addition to maintaining the bridges in the cap itself.
See the OpenMS41 wiki for more info.


X19527 pinout:
4 - .5 BR GND (0670.4-04 ETM pg60)
5 - .5 BR/OR GND (0670.4-13 ETM pg69)
7 - .35 SW/VI/GE (originates at DME X6000-88 to X6002-2 to X6031-4) (0670.5-04 ETM pg82, also 1210.17-10 pg102)
16 - .75RT/WS +12v "Hot at all times" (0670.3-11 ETM pg48)

For the two grounds(pins 4 & 5), I simply connected them both to a ring terminal, and ran them to one of the bolts above the ECU.

For pin 7 K-Line, I pulled the old wire from X6031-4 out of the bundle that crosses the firewall and ran it through the firewall in the DME bundle.

For pin 16, I used a 5A fuse in the aux fusebox and ran a new wire across and through the firewall in the DME bundle. (I also use this as +12v for gauges). For the OBD2 port, it can be +12v hot at all times, or switched, whatever you prefer.
I'm sure there's a way to do this with power from X6002, but I likely snipped that wire before I installed the engine.

[luckysnafu]

It's pretty simple to hook up an OBDII port. You only need 4 wires connected to an OBDII male ended cable. I have mine inside my glove box for easy access and ability to plug in my bluetooth adapter to use Torque on my phone.

OBDII wiring:
Pin 7 - Signal
Pin 16 - +12V (ideally switched with the ignition so it shuts off with the car)
Pin 4 - ground
Pin 5 - ground

The signal for Pin 7 is found on the round 20 pin diagnostic port from Pins 17/20. The wire color should be purple with white stripes (and possibly yellow dashes). Good luck!

[328ijunkie]

We use these. Moving the port to cabin is obviously better but also annoying.

http://www.amazon.com/Elandpower-S-EOLF-BMW20P-Connector-Diagnostic-Adapter/dp/B0054FJEDK/ref=sr_1_1?ie=UTF8&qid=1428376733&sr=8-1&keywords=bmw+20+pin

[Northern]

We use these. Moving the port to cabin is obviously better but also annoying.
http://www.amazon.com/Elandpower-S-E...rds=bmw+20+pin

I have one of those now, but I'd rather wire something in and leave that at home.


I'm thinking I'll run those 4 wires through X6031 along with diagnostic TXD and RXD (since I don't understand what they're for, and I may as well keep them and just let them terminate at the connector if I don't use them)

I'm fine using my peake tool to do SI resets, and the rest just seems like power anyway.

[Sh3rpak!ng]

It's pretty simple to hook up an OBDII port. You only need 4 wires connected to an OBDII male ended cable. I have mine inside my glove box for easy access and ability to plug in my bluetooth adapter to use Torque on my phone.

OBDII wiring:
Pin 7 - Signal
Pin 16 - +12V (ideally switched with the ignition so it shuts off with the car)
Pin 4 - ground
Pin 5 - ground

The signal for Pin 7 is found on the round 20 pin diagnostic port from Pins 17/20. The wire color should be purple with white stripes (and possibly yellow dashes). Good luck!

+1 it's easy to wire up and nice to have in the cabin