What are the OBD-II pins?
Since we don't know what make, model or year your car is, this is a
difficult question. If it is in fact OBD II, the connector should
be located under the driver's side dash.
In order to find your codes, you don't need to plug into the
obd2 port. On the bottom right side of the diagnostic port, there
should be two pins rather close together. My recommendation is to
go to Auto Zone. Some of their stores actually have a key for
checking GM obd1 systems. It looks like a key, and has two prongs
on it that plug right in to where you need to check your codes. If
your local store does not have one, then my advice is to look on
the port and find the two bottom prongs that are closest together
and jump them.
I have the exact same pinout on my 1995 Buick LeSabre. I have
been researching this issue for some time now. The VECI label abve
the radiator in my car states "OBD 1 Certified." However, I believe
this is only stated because the pinouts of the connector are wrong.
I have the VIN L engine, and all technical docs for that engine
point to it being controlled by a PCM. PCMs do not report codes by
flashing the SES light, only GM ECMs do. GM cars with an ECM and a
16-pin J1850 non-OBD-II connector on them, have a pin-out of
4,5,6,9,12,16. You short pins 5 and 6 to receive diagnostic trouble
codes via the Service Engine Soon light. As you can see, those pins
do not light up with our common connectors. Our connectors use pins
4,5,8,9,14,16. What I can tell you about this connector is as
follows: 4=Chassis Ground, 5=Signal Ground, 8=Keyless RF Trigger
(short to 5 to enter program mode), 16=Battery+. (Note 4,5=Ground
16=Battery+ are standard pins for the OBD-II standard. Yet another
thing that points to an OBD-II serial uplink.) 1995 was a
transition year for GM, in many different aspects including OBD-II.
I believe what happened, what the pins were installed in one order
believing that they conformed to standard, and then the standard
changed before finalization. For more information on this, check
out my regular posts to Automotive Forums.com in the Buick LeSabre
forum. This is my latest: