Diagnostic User

Here, there is information for all the users of diagnostic devices.


Before we go deeper into the subject, I would first like to clarify the term OBD. Unfortunately, it changes its meaning depending on the context. Which often leads to confusion in diagnosis beginners. The abbreviation OBD stands for on-board diagnostics. In general, this means that the control units installed in the vehicle (therefore on-board) have integrated a kind of diagnostic functionality. If the results of these diagnoses are to be read out, a device is required. Some of these devices carry the abbreviation OBD in the name, e.g. OBD tool, OBD scanner or OBD tester. For the beginner I would like to mention that an on-board diagnostic tool by no means always drive with the vehicle. It is rather connected in the workshop, in order to find errors more quickly.

In 1988 the California Air Resources Board (CARB) began to define what the "diagnostic functionality" should be in a control unit (ECU) in order to contribute to the "clean air". This definition is called the OBD standard. There was then an extension of this OBD standard, which is called as OBD-II standard or only as OBD-II. (For more details, see OBD-II.)

The car manufacturers already seen the necessity before 1988 to provide the control units with a diagnostic functionality. They were concerned less with keeping the air clean than with the possibility of finding errors more quickly. As you can imagine, this diagnostic functionality has also been given the general term OBD.

The control unit manufacturers naturally also wanted to have a possibility to provide their control units with their own diagnostic functions. Many have also done this and then speak of OBD in this context.


In the following small table, I would like to list again the term OBD in different contexts and show you my nomenclature to avoid confusion.

Context My nomenclature for this context
OBD as a pure abbreviation for on-board diagnostic OBD
OBD within the meaning of the CARB standards OBD-I, OBD-II, EOBD, JOBD
OBD in the sense of the diagnostic standards of the respective vehicle manufacturer MOBD (M for Manufaktur)
OBD in the sense of the diagnostic standards of the respective vehicle supplier SOBD (S for Supplier)



Very often I have heard similar discussions like this.

Person A: "I bought an OBD tool for my Saab."

Person B: "What did it cost?"

Person A: "1000 Euro."

Person B: "This is very expensive, I bought an OBD tool for 20 euros at ALDI and that can be all brands."

Person A and B now discuss for a while. Until both may have realized that A has purchased a MOBD tool and B is an OBD-II tool. The possible functionality of the MOBD against the OBD-II is so enormous, that the price difference can of course be explained, if the MOBD tool uses all possibilities. In order to make it tangible for the newcomer in the diagnosis topic, this is like comparing NewYork to York.


Finally, it should be said that inside the MOBD every manufacturer does what he wants. Thus, it is not very successful, e.g. to use a MOBD tool for Audi on a Volvo.