After long term inactivity and unknown storage conditions, the first thing I would check are the battery connections, ground and B+ connections inside the plastic boxes on the passengers fender and at the engine. Each of the battery cables consists of three terminals on the other end. Then move on to the ECM and BCM connections. Simply unplug and reconnect to get a new fresh connection, terminal spray cleaner optional. Lots of those items operate on lower than system voltage so connections are everything. Of course the wiring itself is subject to damage from vermin, but start with accessible connectors.