Is it possible to read manufacturer specific codes with ELM327

Question

I plan on creating a SW which interacts with the CAN bus (for Cars) over OBDII protocols. The SW will be for PC mainly, and perhaps Android.

However, it is no use if I cannot adapt it to read more codes than what is legislated and "public".

Is it possible to read manufacturer specific codes with ELM327 if you know the adressess and interpretations of them?

Or am I limited to hardware.

I have no knowledge of ELM327, which pins are used etc... I am doing some research here so please be detailed in your answers. Thanks.

BTW, my HW is: ELM327 (chinese v.1,5) with USB cable and Serial COM port to USB drivers on laptop.

Answer 1

Since most CAN communication is done at 500k baud rate an ELM327 will not be able to communicate quickly enough. It would be better off to get a OBDLink SX or possibly build your own hardware (look into the Teensy 3.1 w/ CAN Bus).

Answer 2

This is a tough question (probably the reason why no one attempted to answer it yet). It depends on the vendor and which kind of protocols are implemented by the ECUs in your vehicle. Some ECUs implement OBD2 with custom PIDs – you can easily read these via ELM327 (and friends).

Most CAN-Bus based ECUs implement UDS, which also allows for getting more low level information.

That said, in either case you will need the documentation, since non-standard PIDs and/or DTCs and/or sensor identifiers are completely vendor-specific.