Car died- no lights, no crank, nothing?

With no power to anything on a Jeep I would look at the battery first, the cables and grounds are prone to corrosion. Then I would look at the fuses as they corrode as well. Without testing those first it isn't possible to tell if there is an issue in the power distribution module. Also they usually only fail in segments, like the headlights don't work, or the fuel pump stops. Not common for everything to shut down. Things like the starter have a removable relay that would allow you to test. For instance the no crank tells me it's a power issue, not BCM or even PDM, that is because the system only uses the power feed, ignition switch and wiring with the starter relay in the PDC. The PDC in the image below only has relays and a circuit board with no processors inside it. Not much to fail. First thing I would do is grab a test light and check the fuses in the PDC for power. I would also look at the battery cables especially the ground side. They really love to fail.