2017Express3500/6.0

I purchased this van new in 2017 for a business that never got off the ground. It has 229 original miles. It has been sitting in my driveway for about a year untouched (I know, I know...). It has a new battery and I replaced the starter to rule it out as the issue. The trouble seems to be somewhere between the key and the starter. Vehicle shows no codes on diagnostic tool. Wires appear to be in excellent condition. I’m really scratching my head on this thing. I have a multimeter, but no idea where to start looking for the irregularities in voltage. My thought is to start from the purple wire on the starter and see where it takes me. Any advice or knowledge on this would be greatly appreciated!!

pomerlo

Details are missing here. Does the engine crank but no start ? Or no crank at all ?
Accessories turns on when in ignition ?

2017Express3500/6.0

Engine doesn’t crank at all. There is an audible click in the dash/steering column when the key is in the start position, but nothing from the starter itself. I don’t hear the fuel pump kicking on either when the key is in the on position. All other accessories are functioning as normal. It seems like something is telling it not to send power to engine components. I replaced the starter and tested it. I was able to jump the starter, so it helped me rule out the starter and the battery side of the circuit.

mountainmanjoe

starter relay?

2017Express3500/6.0

I will bench test today.

pomerlo

Yes like MMJ said... first thing to check is the relay.
Next if not successful then I would watch this video to give you some directions. Also some have reported a faulty transmission safety switch or a faulty ignition switch.