OBDII across the world?

Question

Is OBDII consistent across the world?

Any vehicle sold in North America particularly in the United States must conform exactly to all OBDII rules.

What about vehicles that are sold in the US but also sold abroad? For instance imports such as BMW or Mercedes or US made cars that are exported. Do these vehicles continue to conform to OBDII outside of the US and north america?

What about vehicles that were never sold in north america such as Skoda or Citroen? Do these cars also conform to the exact letter of OBDII or is it a more loose implementation of OBDII or do they not use OBDII at all?

Answer 1

I found this informative web site which explains it well:

There are five basic OBD-II protocols in use, each with minor variations on the communication pattern between the on-board diagnostic computer and the scanner console or tool. While there have been some manufacturer changes between protocols in the past few years, as a rule of thumb, Chrysler products and all European and most Asian imports use ISO 9141 circuitry or KWP2000. GM cars and light trucks use SAE J1850 VPW (Variable Pulse Width Modulation), and Fords use SAE J1850 PWM (Pulse Width Modulation) communication patterns.

There is also a list of what cars have OBD-II.

Per WikiPedia EOBD (European on board diagnostics) became mandatory in the European Union in 2001.

Answer 2

Petrol Volkswagen cars sold in the European Union (and VW group cars including Seat, Skoda and Audi) have conformed to OBD II since circa 1995. I don't know the specifics for any other manufacturer but do know that pretty much everything in the UK (including Caterham kit cars) feature OBD II ports.

One difference between EU and US VW's from the late 90's is that the EU cars only feature a lambda probe before the catalytic converter and they don't feature an engine check light on the dashboard. These elements were not required by Euro emission standards.