GM 12 Pin to OBD1 OBD2 16 Pin Connector Adapter Car Motor Diagnostic Tool Cable | eBay

I have a 1995 Cable and Software, can I use this adapter and scan a 1994 with 12pin plug?

 

Probably not. I have ordered two of those from different sources in China; they even looked different. And neither will work as delivered. I made one work by cutting the cable into two pieces, digging out some epoxy-like sealing material from the 12pin end, moving a wire to a different terminal, then splicing them back together differently than supplied. A lot of work.

 

Instead of trying an adapter, you can just use jumper wires. This link is the opposite of what you want to do, but it shows which pins to connect. http://shbox.com/1/xraycable.jpg