[11ford11]

As mentioned you need power to fuse 11 at least
leaving key on is for earlier au to program key to vehicle not your model which requires scan tool and program
rear demist button while in Accessory position is to program remote to vehicle for door

try putting power to fuse 11 from another fuse turn ignition on and see if smartshield light goes out and if it will start
if so fuse box may be faulty - a plug may be out or a alarm of some type may have activated when battery was disconnected and needs bypassing or deactivating with a remote if you have one









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