OBD-II (related to LT1 EFI)

[Mike Fahrion]

>I wonder if there are vehicles out there that have a J1962 16 pin
>socket but are not OBD-II.


Absolutely.  It does add to the confusion.  Many 1995 LT1's were shipped
like this.

The absolute way to tell is by looking at the pin configuration.

>I have a European GM car that appears to be this way (CarComp won't
>work with it) yet the error codes the ECU logs are definately OBD-II
>P0XXX codes.  (It has pin 7 but no pin 10 or 10).

hmmmm - sounds like an iso9141 configuration - what model/year car?  Where
was it mfg'ed?  How are you reading the error codes?

I am trying to add as much relevant information as I can on this subject to
our web site at www.obdii.com.

It does seem like there is a large fuzzy line during the transition to obdii
where it was gradually phased in.  Obviously its a little easier to tell in
the states.

>I have noted on the Actron site that they have a NON-OBD-II  ScanTool
>that works with US GM vehicles, some of which need a special 16pin
>J1962 adaptor cable. The OBD-II module is a separate option for a
>different list of cars again..
>
>So it looks to me that some manufacturers are fitting the J1962
>connector (presumable for standardisation reasons) but not
>implementing the OBD-II protocols unless they are forced to
>(which in Europe they do not have to...yet!).
>
>The question remains about my GM vehicle... is it perhaps OBD-I or a
>GM proprietary protocol ?
>Is OBD-I as well defined as OBD-II  (and where is it defined).
>
>regards,
>
>Martin
>-----------------------------------------------------------
>martin at mgass.demon.co.uk
>-----------------------------------------------------------
>