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Help with OBD

People often write asking where they can get more OBD information, or for help in making their circuits, etc. The sections shown above provide answers to most of the common questions that we receive. Perhaps the most popular question of all is:

What OBD protocol does my car use?

There is a chance that your car may not use any. Not all vehicles use standard OBD (On Board Diagnostics) protocols, so do not be surprised if yours does not. If your car is older, or from a country that does not require OBD, then your car will likely not respond to OBD requests for data.

It is difficult to provide an accurate date after which vehicles will respond to OBD commands, as most counties provide a 'phase-in' period in which the OBD requirements increase over time. With the help of our users and from published information, we have been able to come up with the following list of dates for light duty vehicles:

  • Argentina - 2009
  • Australia - 2006 (gas), 2007 (diesel)
  • Bolivia - 2016? (imports)
  • Brazil - 2007 (gas)
  • Canada - 1998
  • China - 2008 to 2012
  • Chile - 2013 (diesel), 2014 (gas)
  • Colombia - none
  • European Union - 2001 (gas), 2004 (diesel)
  • Hong Kong - 2006 (gas), 2009 (diesel)
  • Indonesia - 2016?
  • Iran - 2012
  • Israel - 2003
  • India - 2010 (some), 2013 (more)
  • Japan - 2002 (basic), 2008 (domestic), 2010 (imports)
  • Malaysia - 2015?
  • Mexico - 2006 to 2013
  • Morocco - 2011
  • New Zealand - 2006
  • Peru - 2016?
  • Russia - 2010
  • Singapore - 2014
  • South Korea - 2005 to 2010
  • Taiwan - 2006 (diesel), 2008 (gas)
  • Thailand - 2013
  • Turkey - 2013
  • USA - 1996
  • Venezuela - none
  • Vietnam - 2017?

Cars and light duty trucks that were manufactured for sale in the listed country after the date shown will likely work well with our products. If your vehicle is older than this, or was imported, it may not be OBDII compliant so may not work with our integrated circuits (even if it uses a similar looking connector). Note that large trucks and busses generally have different OBD requirements, and typically use different protocols (usually SAE J1708 or SAE J1939).

Vehicles that comply with the OBDII standards will have a data connector within about one meter of the driver's position. Check the owner's manual for information on its location as newer manuals often provide this information. In most cases, it will be in plain sight at the bottom of the dashboard, but occasionally it will have a cover that needs to be removed, or moved sideways (there are a few vehicles that have the connector behind a panel in the centre of the dashboard).

The OBD connector is officially called an SAE J1962 Diagnostic Connector, but is also known by DLC, OBD Port, or OBD connector. It has positions for 16 pins, and looks like this:

J1962 connector

Be careful, as many vehicles that do not comply with the OBDII standards may still use the J1962 type connector for data, but do not use a standard OBDII protocol for the data exchange. These may appear as if they should work, but they will not (and you may cause damage to the circuits if you connect the wrong voltages to them).

Locate this connector in your vehicle and determine if wires are in pins 2, 6, 7, 10, 14 or 15. Once you know which pins are used and which are not, then determine which standard applies to you using the following table:

Pin 2Pin 6Pin 7Pin 10Pin 14Pin 15StandardUse
must have--must have--J1850
must have-----J1850
--must have--may have*ISO
-must have--must have-ISO
* not all ISO9141 or ISO14230 vehicles use pin 15 (the 'L' line)

The above should be considered a good guideline. The presence or absence of wires in the connector is not an absolute indication though, as only your vehicle manufacturer can say for sure which standards the vehicle was built to.

Pre-2008 Typical Protocols

New cars (2008+) now generally use the faster ISO15765 (CAN) protocol, but older vehicles might have used one of several. The protocol used by a particular manufacturer was generally consistent, but is not guaranteed to be so (for example, Chrysler started using ISO9141 and switched to J1850 around 2000). Typically, you will find the following standards usage for older vehicles:

(ELM327 or
Acura  X 
Chrysler XX 
General Motors X  
Honda  X 
Saturn X  
Subaru  X 
Suzuki  X 
Toyota  X 
Volkswagen  X 

Actually, beginning with the 2005 model year, some North American vehicles did begin using the ISO 15765-4 (CAN) interface standard, so maybe we should have put some 'X's in the last column. The above should be a good starting point for you, though.

Beginning with the 2008 model year, all North American vehicles were required to use ISO 15765-4 (CAN).