Pinpoint Test D: DTCs B1600 and B2431 - The Passive Anti-Theft System (PATS) Ignition Key Transponder Signal Is Not Received or the Transponder Programming Failed (Damaged Key or Non-PATS Key): Notes
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
Refer to SYSTEM WIRING DIAGRAMS (Escape) or SYSTEM WIRING DIAGRAMS (Mariner) for schematic and connector information.