Will not crank and Security lock is blinking

Hello,
A common cause for that system to activate is a low or week battery. Try to get a charger on it and let me know what happens.

These guides will help you fix it

https://www.2carpros.com/articles/car-battery-load-test

and

https://www.2carpros.com/articles/how-to-reset-a-security-system

Please run down these guides and report back.

Tom

Hello,
How did you make out with the battery, was it low? Another thing that can be an issue is the key, Has there been any new keys made for your car? Have you been having any issues with the alarm system turning on or off or has that been working properly. You can try to lock then unlock the drivers door and the truck with the main key not the valet key. Let me know if the alarm system turns on and back off normally.

Good afternoon,

Just wanted t add my 2 cents.

The security pops up when you either had a battery disconnect or a dead battery.

With Ford products, resetting the security is not easy. You need the IDS program or a scan tool that can reset the security system.

If you do not have the scan tool, you can call a locksmith and have them come to you and reset the system for you. You have to have a security license for Ford products.

Roy