2002 Magnum Wiring/Security ?
Doesn't sound like your cranking issue is security to me, I would double check all of the power and grounds from the ignition switch and relays first. If you pull the relay and jump the 30 and 87 terminals in the box it should crank over even if the security is keeping it from running. If it doesn't crank you know it's either in the power to the fuse box, small wire or connections to the starter, or a ground issue.