I have a '94 Buick Park Avenue and the service engine light is on. It is an OBD1 car, but has the octagonal OBD2 connector as do many '94 and '95 GM products. I work at a Lexus dealer and have tried 5 different non Lexus scan tools from a $99 cheapie to an expensive one and can't read the PCM. The ones with the octagonal connector don't give a choice lower that '96 model year and won't read it, and the ones with OBD1 software wont connect to the car. Am I stuck going to a GM dealer and getting it scanned with a Tech 2, or is there another option? I know how to use a paper clip on an OBD1 connector, but does that work with OBD2 as well and if so, how? All replies appreciated.

OBD 2 became mandatory in 96 i beleive...so your buick will probably only talk to a scanner with and obd 1 connnector. it is rectangle shaped with two rows of pins. any independent shop should be able to scan it. Most use a snap on scanner Mt 2500( the red brick) or a MODIS which does pretty much everything. Hope you get it sorted out. The OBD 1 connectors need to be powered up by a source like the cig lighter or equivalent. OBD 2 connectors provide power to the scanner.
Any driveablility issues with the Buick? These older cars always throw erroneous codes like " code 42 Est timing problem. No issue, but the light is on. Keep us posted!

Is is a problem with the scanners or is the cars computer not comunicating. If you have tried so amny scanners i have to wonder if the problem may be on the cars side.

Dave,
Take it to an Auto Zone parts store. They'll scan it for free...in the hopes that you will then purchase the needed part from them. ;)

I am familiar with the differences between OBD 1 and 2, and the conector differences. But some '94 and '95 GM cars had OBD1 with the octagonal connector. I guess no aftermarket scanners will read this combo, including the Autozone I tried today, Bill ;)
I'll probably have to take it to the Buick dealer and pay diag time for them to use the Tech2. Thanks.

i think you can still do the "paperclip" scan on those cars, but i don't know which terminals to jump together.