This is my first time posting here so hopefully I’m doing it right.

I have a 2003 Dodge Cummins, I started it 2 weeks ago, and it just up and died like I shut the key off, all my warning lights came on and my gauges all stopped working, after messing with it I noticed I have no grid heater, no lift pump, and no sound of the injectors clicking, my obd 2 port no longer works, I’ve checked all power to the ecu, all my grounds are good, I unhooked the batteries to reset the system, after it sitting fo about an how there was nothing, I did some more testing and decided to order a front control module, from research I guess these can be a common issue, replaced that today, it didn’t change anything. I took a test light and did a test for shorts, found out that on the fuse for my guage cluster and my obd 2 lit up the test light when it shouldn’t have, showing there was a possible shirt according to what I learned online, so I traced all the wires and inspected them, came back with nothing, I tested it with a multi meter and found out that without a fuse in the slot, there’s power on both prongs, very little power on one side and 12 volt on the other, I thought that was weird, so I pulled the cluster, replaced it with one out of a parts truck and bam, as soon as it’s plugged in I have my lift pump, grid heater and everything that wasn’t working before, but that is with the key out of the ignition, I turn the key on and nothing changes and I have no gauges and it won’t even crank now, I’m leaning towards the cluster is shot and the new one isn’t working because it needs to be programmed to the truck, anyway, if anyone could shed some light or share your experiences, I’m already many hours into this and I can’t think of what else to try. Thank you