Perhaps the scanners use batteries, or the strider. Since these are both mechanical then they obviously need some form of power. Maybe you will find an ammo stash with decommisioned scanners and a few batteries laying about. or maybe a wall charger for the scanners. Just a thought.
In OpFor's bootcamp the drill sergeant says that the PCV will can recharge via standard HEV outlets, military PCV outlets, and commercial outlets. Maybe City 17 will have some of these commercial outlets scattered around.