Top Tips: OBD-II, EOBD, EOBD2 - what's the difference?

What is "EOBD"?

EOBD is an abbreviation of European On-Board Diagnostics

All petrol cars sold within Europe since January 1st 2001 and diesel cars sold since January 1st 2004 must have on-board diagnostic systems to monitor engine emissions.

These systems were introduced in line with European Directive 98/69/EC to monitor and reduce emissions from cars. All such cars must also have a standard 16-pin EOBD diagnostic socket that provides access to this system.

As a result of this it is now possible for a home user, enthusiast or small garage to afford low-cost tools such as our GCR05 and GCR10 code readers to read engine management fault codes, where previously very expensive workshop tools or a trip to the dealership would have been required.

What are OBD-I, OBD-II and EOBD2?

On-Board Diagnostics, or OBD, was the name given to the early emission control and engine-management systems introduced in cars. There is no single OBD standard - each manufacturer often using quite different systems (even between individual car models).

OBD systems have been developed and enhanced, in line with United States government requirements, into the current OBD-II standard. The OBD-II Federal requirements apply to cars sold within the USA from 1996, but do not apply to cars sold outside the USA - even those made by American manufacturers.

EOBD is the European equivalent of the American OBD-II standard. The two are essentially the same, but the European standard was implemented much later, and applies to petrol cars sold in Europe from 2001, diesels from 2004.

EOBD2 is not a new version of EOBD.
EOBD2 tends to refer to manufacturer-specific features available on some OBDII/EOBD tools to access additional parameters/information from a car, over and above the normal parameters and information available within the EOBD/OBDII standard. There are, as such, no 'EOBD2 cars', i.e. cars that require an EOBD2 tool to access their diagnostics information.

EOBD Languages

Although EOBD is a standard, it is not a single 'language', but a combination of 5 main languages. Different car manufacturers use different languages when their cars speak to diagnostic tools. Almost all of our tools speak all of the languages, so you don't need to worry about working out which the car is using. The languages are listed below:

• PWM - This was the language used on most petrol Ford cars from 2001 (and some back as far as 1997) up to around 2003.
• VPW - This is the language used on many Chrysler and Isuzu vehicles.
• ISO9141-2 / KWP2000 - ISO and KWP were the languages used on most other European and Asian vehicles from 2001 for petrol, 2004 for diesel. Both use the same connections on the EOBD port.
• CAN - CAN (or Controller Area Network) is the newest and fastest system, and should be used on all new cars from 2008. Many manufacturers have been migrating their cars to CAN since around 2003.

Most tools support not only the CAN language but also the other EOBD languages listed above. All of the Gendan range of handheld EOBD code readers such as our GCR25 will cover all the EOBD languages.

What does EOBD offer from a car?

EOBD tools are able to read fault codes relating to engine management and emissions faults on a car. These fault codes can either be 'generic' (i.e. the same definition applies to all car manufacturers) or manufacturer-specific. Generic codes generally begin with P0 and Manufacturer-specific codes with P1.

Many of our advanced testing tools provide code definitions to both P0 and P1 codes.

In addition to a fault code, EOBD standards allow the more advanced test equipment, such as our EngineCheck Pro system, to display readings from the engine sensors, e.g. RPM, Throttle position, Oxygen sensor voltages, temperature sensor readings.