Integrating an OBD2 port into your BMW E30 after an M52 or S52 engine swap is essential for diagnostics and tuning. This guide provides a clear walkthrough on how to wire an OBD2 port, focusing on the X19527 connector and its integration with the E30 chassis and swapped engine harness. Understanding the correct “Obd2 Port Wiring” is crucial for a successful and functional installation.
For this process, we’ll reference key connectors and electronic troubleshooting manual (ETM) pages to ensure accuracy. The main connectors involved are:
- X19527: The E36 OBD2 port connector itself.
- X6000: DME (Digital Motor Electronics) connector.
- X6002: Underhood 20-pin ADS connector.
- X6031: Smaller connector near X20 and X69 on a stock OBD2 M52/S52 harness.
Let’s break down the “obd2 port wiring” for each pin on the X19527 connector based on the provided information.
X19527 OBD2 Port Pinout and Wiring:
- Pin 4 – Ground (Brown wire, .5 BR): Connect to chassis ground.
- Pin 5 – Ground (Brown/Orange wire, .5 BR/OR): Also connect to chassis ground.
- Pin 7 – K-Line (Violet/Yellow/Gray wire, .35 SW/VI/GE): This connects to the DME for diagnostic communication. It originates from DME X6000-88, goes to X6002-2, and then to X6031-4.
- Pin 16 – +12V Power (Red/White wire, .75RT/WS): Needs a constant +12V power supply.
Step-by-Step OBD2 Port Wiring Instructions:
-
Ground Connections (Pins 4 & 5):
- Bundle the brown and brown/orange ground wires together.
- Attach them to a ring terminal.
- Securely bolt the ring terminal to a convenient chassis ground point, such as one of the bolts near the ECU.
-
K-Line Connection (Pin 7):
- Locate the Violet/Yellow/Gray K-Line wire (originally at X6031-4).
- Instead of routing it back to its original location in the engine harness, extend this wire.
- Run the extended K-Line wire through the firewall, ideally within the DME wiring bundle for a clean installation.
- Connect this wire to Pin 7 of the X19527 OBD2 port.
-
+12V Power Connection (Pin 16):
- Install a 5A fuse in your auxiliary fuse box for protection.
- Run a new Red/White wire from the fused power source.
- Route this wire through the firewall alongside the DME bundle.
- Connect this +12V wire to Pin 16 of the X19527 OBD2 port. This provides constant power to the OBD2 port.
Important Notes:
- Flashing ECU: For ECU flashing, bridging pins 14 and 18 at connector X6002 is necessary in addition to the standard OBD2 port wiring. Refer to the OpenMS41 wiki for detailed instructions on enabling write access.
- Power Source: While this guide suggests a fused +12V source, alternative methods involving tapping into power from X6002 might exist. However, ensure proper wiring and fuse protection in any configuration.
- ETM Reference: Consult the ETM (Electronic Troubleshooting Manual) page 87 for X6002 pinout and X19527 picture, and relevant pages mentioned for wire colors and origins.
By following these “obd2 port wiring” steps, you can successfully integrate a functional OBD2 port into your E30 M52/S52 swapped BMW, enabling diagnostics and engine management access.
