OBD II BeagleBoard Interface?

This is where the meat of the system will be. The BB can interface with OBD II with several methods (theoretically). Many consumer level products are already available to interface OBD II with a computer.

Let’s start by examining how this can be accomplished. Most automobiles (light passenger vehicles) manufactured between 1996 and 2008 have a J1962 OBD2 style connector which has a pin out as follows.

Example PLDL

The protocols are well known and there is open source software hardware available to communicate with OBD II. The newer protocols are even easier to handle.  A good website for information on interface hardware can be found here.  The reason why OBD II is not very straight forward is because there are so many different types of vehicles.  Even though many vehicles sold in the United States and elsewhere contain the above pictured connector there is differences. These differences are the result of technological progress and vendor implementation. The BB can communicate with OBD II with a serial/usb to OBD tool. The expansion header on the BB also lends itself to OBD II communication. There is even a Bluetooth and WiFi OBD II interface here. We have multiple options to interface, now we need to get them to talk and display relevant data and respond to our commands.

On a related idea from www.beaglesride.org…   A vehicle with a Power-train Control Module (PCM) can also be directly manipulated using a BB. Some vehicles have a PCM module that contains all the logic to operate the engine under various conditions. A single EEPROM or other “chip” type on the PCM can be easily re-flashed with a new “map” altering key operating parameters. Companies like SuperChips have devices that can reprogram the vehicles power-train computer.