GM DTC Error Code

I own a 1996 Chevrolet 3/4 ton pickup with a 350 engine, 5 speed manual. I have an error code P1192 - undefined. Has anyone ever seen this error code or does anyone know what it means?

It means totally different things for different models (for BMW it’s “post-trim catalyst fuel system”; for Chrysler “Inlet air temp, circuit low”, and so on), but the best I could find for your case was “Voltage External”.

Anyone have some idea as to what this means? Maybe some sort of problem with the electrical system?