Suburban dilemma

Owned by the federal government.. They may have installed some emergency equipment (blue lights, wig wags, radios, sirens, etc..) that created the interruption of a circuit. It could be related to that. I had an old Harley that had an intermittent no start/no run condition. I traced it to a wire that ran to the coil. When I turned the handlebars it would interrupt the circuit. You may have an issue in the steering column. I had a city vehicle, a Durango, that had an issue and it was a wire in the steering column. Tilt the steering wheel and it would break the circuit. I also had a Chevrolet Impala (city vehicle) that would just suddenly cut off and loose all lights and everything. Obviously would not start. It was traced to a short on a wire bundle that went through the firewall. I hope you get it fixed. The 2500 Burb is a great vehicle.