People often write asking where they can get more OBD information, or for help in making their
circuits, etc. The sections shown at the left 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.
Some regions passed laws requiring OBDII compliance many years ago, while others have only recently
required it. It is difficult to come up with a truly accurate list, but here are the approximate Model
Years for when laws came into effect for light duty vehicles:
- Argentina - 2009
- Australia - 2006 (gas), 2007 (diesel)
- Brazil - 2007 (gas)
- Canada - 1998
- China - 2009
- Chile - 2013 (diesel), 2014 (gas)
- European Union - 2001 (gas), 2004 (diesel)
- Hong Kong - 2006
- Israel - 2003
- India - 2010
- Japan - 2002, 2008 (JOBD)
- Mexico - 2006
- Morocco - 2011
- New Zealand - 2006
- Russia - 2012
- Taiwan - 2008
- Thailand - 2013
- USA - 1996
Cars and light duty trucks that were manufactured for sale in these regions (ie not imported), will
likely work well with our products. If your vehicle is older than this, it is likely not OBDII
compliant, even if it uses a similar looking connector. Note that large trucks and busses generally
have different requirements, and use different protocols (usually SAE J1708 or SAE J1939).
We are not referring to them in this discussion.
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:
Be careful, as many vehicles that do not comply with the OBDII standards do occasionally use the
J1962 type connector for data, but do not use a standard OBDII protocol for 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 2||Pin 6||Pin 7||Pin 10||Pin 14||Pin 15||Standard||Use
|must have||-||-||must have||-||-||J1850 PWM||ELM320
|must have||-||-||-||-||-||J1850 VPW||ELM322
|-||-||must have||-||-||may have*||ISO9141-2|
|-||must have||-||-||must have||-||ISO15765-4|
* 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.
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
|Acura|| || ||X|| |
|Chrysler|| ||X||X|| |
|Ford||X|| || || |
|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).
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