Has anyone ever worked with the GM OBD1.5 system and can recommend a compatible scan tool that would work with this system? The vehicle that I am working with is a 1995 Pontiac Sunfire with the 2.2L four cylinder engine and automatic transmission. The diagnostic connector under the dash is physically an OBD2 connector, and my OBD2 scan tool will plug into it, but because the car is pre-1996 the scan tool doesn't work well with it. If I manually select my vehicle information as a 1996 Sunfire, all it will attempt to access are ABS and SRS systems. My current scan tool is a Launch Millennium 70
I had a similar issue communicating with a 1995 Chevrolet Blazer. It has a OBD 2 connector, but OBD 1 computer protocol. I used a GM Tech-2 Scanner and I could communicate with no issues.
The only aftermarket scanner that was compatible with this 1.5 system was snapon. We had the Red Brick, and later the original Modis that was capable of connecting fully to those systems. Not sure if the OTC Genisys scanner was compatible. We had a Genisys in the shop but I never attempted to connect using it.
Be aware also, that each manufacturer had some early OBD2 systems in testing on production models as early as 1994 that used the standard OBD2 DLC. These vehicles were only partially compliant to OBD2 and were usually missing the EVAP system OBD2 function as it was still being developed. I owned a 1995 Toyota Tacoma years ago that fit this category
Also, on the OBD 1,5 systems, I was told they used the OBD2 DLC instead of the GM 12 pin OBD 1 DLC due to phasing out the OBD1 12 pin connector and not wanting to have unused 12 pin DLC onhand when OBD2 was officially mandated in 1996
Hope this helps
Last edit: 3 years 11 months ago by Nelson60. Reason: updated info
Genisys worked on these systems and was really good for pre obd2 gm as well.
I had one and it worked pretty good it had bi-directional functionality
pre obd2.
(Remember there were three makers of the tech2 Bosch, Vetronix and OTC
so yes they had good access and knowledge of GM and put it into the Genisys.
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