How do you disable the antitheft system in a 2004 Lincoln navigator without the key the key

Mobile Locksmith to reprogram the lock system and engine immobilizer / alarm system.

https://www.google.com/search?q=mobile+locksmith+near+me

..

There is no reset on a FORD PATS system. If the theft light is rapidly flashing, get the trouble codes read and fix it.
Ford PATS Antitheft System Ricks Free Auto Repair Advice

If you could disable it, it wouldn't be called anti-theft.

The security, antitheft or lock picture/icon is a visual indication that something in the car's antitheft system is failing. In most GM cars and trucks there is a hidden system that most people are unaware even exists. From the moment you put your key in the ignition, there begins a constant line of communication between your key's security chip or transponder, to the ignition's lock cylinder, and then to the car's TDM (Theft Deterrent Module). These 3 parts are in CONSTANT communication. If the key is in the ignition, then these parts are sending signals to each other. The security light illuminates when that signal gets broken, even just for a second. When the signal breaks, the car misinterprets this as an attempt at theft and goes into antitheft mode. The car thinks its being stolen or hotwired because it is not getting that signal from YOUR specific key. This is why the security light turns on and shuts down your vehicle. This link explains it pretty well.
http://www.diy-gm-security.com/

reset to factory settings.

start with fully charging your battery.

sounds like antitheft system is acting up..needs reprogramed maybe..pull the negative cable with the key on....kills everything..then shut the key off..reconnect the negative.. turn the key to run position for a few seconds(resets all factory presets) see if it will start..

Your keep cranks. The problem is not on your battery now but your key system. Please check the key, housing, wiring and relays for malfunction.

if you read your owners manual all those questions could be answered. you can do this instead of asking someone to scan it and print it here where you will still have to read it and you won't have pictures. stick with a dealer for replacement keys.

Turn the key forward a notch then it should come out. If you are turning the key all the way off it enables the accessories (radio etc), locks the key in the ignition and disables the gear shifter.
If thats not the case then there is a button to be depressed so that the key can turn anticlockwise>off another click and the key can be removed.
It'll be one or the other....faulty ignition lock is the only other diagnosis