Question: The Service Engine Soon light came on on my car, which is a 94 Buick Century with the 3.1 V6 engine.
Here is the problem I am having. Up until 1993, you could read the codes on all of the GM cars by jumping the A and B terminals on the ALDL connector under the steering column.
Then in 1996, all of the cars became OBDII and you use an OBDII scan reader to get the codes.
Somehow, 1994 and 1995 are “in between” years. I still have the 12 pin connector under the steering column that looks like the same connector as the 1981-93 connectors, only it isn’t, because only 4 of the 12 pins have electrical contacts in there. You can’t jump the A and B terminals on a ‘94 GM car and get the codes, but you also can’t use an OBDII scanner because the connector is a 16 pin connector instead of 12 pin.
What can I do here? Is there some special code scanner I can get? If there is, I haven’t been able to find one. Is there some other method for getting the codes from these cars?
Thanks.

You need to find an OBD I compliant scanner. Google OBD I. Call some local garages and see if they can read it for you. The odd vehicles used the 16 pin connector but not OBDII compliant hardware. This system was present on the 94-95 GM H-body cars, 94-95 Buick Regal, 95 Lumina, 95 Monte Carlo, 94-95 Grand Prix, 94-95 Cutlass Supreme, Chevrolet Beretta/Corsica 94-95, 94-95 Corvette, 95 Camaro and Firebird, Cavalier, Sunfire Buick Skylark, Achieva, Grand Am.
You can find an mt2500 with the older cartridges on ebay for $200 to $300. Not only will it give you codes but a very good data stream as well.

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