2000 Chevrolet Silverado 4.3L Engine P1345 Fault After Spark Plug and Distributor Replacement

I recently replaced the spark plugs, wires, distributor cap, and rotor in my 2000 Chevrolet Silverado with a 4.3L V6 engine. Before replacing components, I removed the distributor to service the rotor and cap. I set cylinder #1 to Top Dead Center (TDC) and aligned the distributor rotor with the triangle mark on the gear. Since then, the truck has started throwing diagnostic code P1345. Does this require a scan tool to adjust the timing? Is there a possibility that the timing was misaligned during reassembly?