The instrument cluster acts pretty much like your brain. I'm not saying that the cluster is your issue, just clarifying somewhat.
Your brain tells your body what to do, in turn your body reacts. However, if you touch something hot (your hand for instance) sends a signal to your brain to let go.
If you have bad communication between your brain and hand (we'll say nerve damage) your brain doesn't have a clue as to what's going on, and needs signals from your body to perform properly.
Therefore, if there's a problem with the internal BCM/FCM, you can turn the key and the cluster isn't getting the required signals it needs to perform specific tasks it cant communicate back to the truck what to do.
Not exactly on point, but I think you get the general idea.
It was quite common on the older Chrysler models (Caravans/Voyagers and some Mitsubishis) than the contact points next to the plug on the back of the instrument cluster would become weak and break (severing the nerve) and they wouldn't start/run). Take a look at this thread for reference: http://www.ramforumz.com/showthread.php?t=141037