cummins isb engine will not shut down

Took steering column apart, found no suspect wiring. Started up and turned ignition key off. Still running. I then removed the wiring plug from back of ignition switch to rule out switch. Still running. I then checked for voltage at the wires on the ignition plug expecting to find voltage only at battery terminal. Instead I found voltage at battery, ignition, and G1 terminals.
Does this sound normal, or am I getting crossover from other wiring?
Thanks for the interest in my predicament!