For BMW enthusiasts and DIY mechanics, accessing your car’s hidden potential through coding and diagnostics is a rewarding endeavor. Typically, this requires an Ethernet To Obd2 Cable, also known as an ENET cable. While these cables are readily available, import restrictions or simply the desire for a hands-on project might lead you to consider making one yourself. Fortunately, crafting your own ENET cable is a straightforward project achievable at home with a few basic tools and components. This guide from obd-de.com will walk you through each step, ensuring you can connect your BMW to your laptop for coding and diagnostic purposes without breaking the bank.
Parts You’ll Need for This DIY Project
Before we begin, gather the necessary tools and components. You can find these items at most electronics retailers or online marketplaces like Amazon. Here’s what you will need:
- Soldering Kit: Essential for creating secure and lasting electrical connections.
- Example: Soldering Kit
- Multimeter: Used to test the resistor and ensure correct electrical flow.
- Example: Multimeter
- Ethernet Cable (10 Feet): A standard Cat5e or Cat6 Ethernet cable will work perfectly.
- Example: 10 Feet Ethernet Cable
- OBD2 Connector (Male): This connector will interface with your BMW’s OBD2 port.
- Example: OBD 2 connector
- 510 Ohm Resistor: A crucial component for proper communication in BMW ENET cables.
- Example: 510 Ohm resistor
- Optional Combo Kit: For convenience, you can get a combo kit containing soldering tools, a multimeter, and cutters.
Step-by-Step Guide to Building Your ENET Cable
Follow these steps carefully to assemble your Ethernet to OBD2 cable.
Step 1: Prepare the Ethernet Cable
Begin by cutting your Ethernet cable in half. This gives you two ends to work with, and for this project, we only need one half. Slide a cable protector and boot onto the cut end of the Ethernet cable. These will provide strain relief and a professional finish to your cable.
Step 2: Expose and Prepare the Ethernet Wires
Carefully remove the outer plastic jacket of the Ethernet cable to expose the internal wires. You’ll see eight wires, each with a different color. It’s important to identify each wire’s color and corresponding pin number in the Ethernet standard (T568B is commonly used). Tin the exposed tips of each wire with solder. This pre-soldering process makes it easier to connect them to the OBD2 connector later. For this DIY ENET cable, we will not need pins 4, 5, and 7 of the Ethernet cable, which typically correspond to the Blue, White/Blue, and White/Brown wires. You can cut these wires off to avoid confusion.
Step 3: Open the OBD2 Connector
Carefully open the OBD2 connector. It typically comes in two halves. Inside, you will see 16 pins arranged in two rows, eight pins on top and eight pins below. These pins are numbered 1 to 16. You will be soldering the Ethernet wires and the resistor to specific pins on this connector.
Step 4: Test the 510 Ohm Resistor
Before soldering the resistor, use your multimeter to test its resistance. Set your multimeter to measure resistance (Ohms) and check that the resistor value is within the range of 506-560 Ohms. This ensures the resistor is functioning correctly and will provide the necessary termination for the ENET communication.
Step 5: Wiring and Soldering – Connecting Ethernet to OBD2
Refer to the pin diagram below to understand which Ethernet wire needs to be soldered to which pin on the OBD2 connector. This is crucial for correct communication. Solder each tinned Ethernet wire to the corresponding OBD2 pin as indicated in the diagram.
Here’s a table summarizing the connections for clarity:
| Ethernet Pin # | Wire Color | OBD2 Pin # |
|---|---|---|
| Pin 1 | White/Orange | Pin 3 |
| Pin 2 | Orange | Pin 11 |
| Pin 3 | White/Green | Pin 12 |
| Pin 6 | Green | Pin 13 |
| Pin 8 | Brown | Pin 4 & 5 |
Finally, solder the 510 Ohm resistor to Pins 8 and 16 of the OBD2 connector. This resistor is essential for the proper operation of the ENET communication protocol.
Final Steps
After you have soldered all the connections and the resistor, carefully close the OBD2 connector cover, ensuring no wires are pinched or exposed. Your DIY Ethernet to OBD2 cable is now complete! Connect it to your BMW’s OBD2 port and your laptop to begin coding, diagnostics, and unlocking the full potential of your BMW. Enjoy the satisfaction of using a cable you built yourself for advanced car customization and maintenance.
