I tried Mike's OBD1/OBD2 scanner on the car, and got wildly different readings depending on what year and VIN code I picked. According to information on
this site, the VIN code for a 1993, 1994 and 1995 3800 engine is L or 1. From what I found elsewhere, 1 is the code for the supercharged version, so I used L. In 1995, they also added VIN code K for the 3800, but there is still L and 1, so I'm not sure what K is.
Anyhow, if I set the machine for 1994 VIN L or 1995 VIN L, it says there are no DTC codes in the ECM. If I set it to 1993 VIN L, I get a boatload of DTC codes, including one for PROM error and some that don't make any sense. I'm inclined to think that the 1993 result is closer to the truth.
If I set it to 1995 VIN K, it says that it can't read the system.
And in any case I have to use wires, as in this picture, because the OBD2 connector only works with OBD2.