Later after I’d just finished the mission An Act of Piracy – the one where you steal the Bavarium Shielded Tank to get supplies Mario’s recovery – lo and behold afterwards I opened the map and what do I see but another yellow bull (mission) called Electromagnetic Pulse.
Start the mission, you get the briefing, “Follow pipes” says Dimah.
Follow the pipes, and kill the boats and soldiers where they stop. Follow the “Reach” prompt which takes you underwater, then inside to blow up 3 large machines powering the EMP FOW. Escape, you are done … no regional FOW EMP attacks on your vehicles anymore!