How to Connect an OBD2 to Your Car

by Contributor

All cars sold in the United States after 1996 are required to be equipped with an OBD2 system. The OBD2 system monitors a car's performance and alerts the driver of current problems, as well as potential problems. An OBD2 reader has to be connected to the car in order to retrieve the Diagnostic Trouble Codes (DTC) generated by the OBD2.

Determine whether your car is OBD2 compliant. A car that is OBD2 compliant will have a female 16-pin connector on the driver's side near the center console. Petrol vehicles manufactured as of 2001 and diesel vehicles manufactured as of 2004 should have this connector.

Prepare the equipment you will need. Depending on the type of OBD2 reader you will be using, you will need a personal OBD2 code reader and a cable, or a computer with OBD2 software, a converter and connectors (see Resources below). For your safety, your car engine must be off while you connect your OBD2 reader.

Locate the 16-pin connector. This connector is not always easy to find but it will be inside the car and not under the hood. Some places where car manufacturers install this connector include: under the steering wheel, the driver's foot well, the area between the driver and passenger seat, behind the ash tray, under the passenger seat, and over the passenger door.

Check the connector for the available pins. The connector must have pins 4 and 5 for grounding and pin 16 for power supply from the battery. The other pins are present for the various protocols required for different vehicle brands, including SAE J1850, ISO 9141-2, ISO 14230 and CAN bus.

Connect your OBD2 code reader. Plug the end of the included cable with the 16-pin connector to the female 16-pin port, and then connect the other end of the cable to the OBD2 reader.

Use your laptop computer as an OBD2 code reader. You can connect your computer to your car with the use of a USB, RS-232C or Bluetooth connector. In addition to connectors, you will need the OBD2 software to retrieve the information from your car and converters to modulate the voltage (see Resources below).

Tip

  • check When choosing a converter to use when connecting your computer to your car, be aware that the converters vary according to the protocols available. These include ISO15765, ISO9141-2, ISO14230PWM, J1850-41.6 and VPW J1850-10.4. Each converter is designed to work with just one of these 5 protocols.

Items you will need

About the Author

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