Ford F150 Theft Light Blinking Won't Start: Causes & Fixes

Ford F150 Theft Light Blinking Won’t Start: Causes & Fixes

The vehicle stability control, instrumentation,  anti-theft system, and engine management system in your Ford F-150 are just a few of the high-tech electronic components in your truck. Unless something goes wrong, we rarely give these critical components a second thought.

The anti-theft system is one of the most commonly overlooked systems. In this section, we’ll explain why your Ford F150 theft light blinking won’t start and how to reset it if it malfunctions.

Ford F150 Theft Light Blinking Won't Start: Causes & Fixes

What Your Anti-Theft System Is And Does

A Passive Anti Theft System (PATS) is an engine immobilization system and alarm that is installed in the Ford F-150. To prevent your truck from being stolen, it has an integrated key head transmitter that prevents the engine from starting without the correct code. This type of key is also called a transponder key or a chip key.

Electronically-programmed transponder keys come with your truck and allow you to start and stop it. The system will not recognize any other key and the engine will not start if you try to start your vehicle with it. Additional keys, on the other hand, can be purchased and easily programmed by the user.

When PATS is activated, an anti-theft warning light will flash every two seconds as a deterrent and display that the system is working. When the ignition is turned on, the light will illuminate for three seconds before going out. There is a problem if the light keeps on or flashes frequently.

The Anti-Theft System Has Issues


Occasionally, PATS issues can cause the alarm to go off, preventing you from starting your truck. Thunderclaps and other loud bangs can also set off the alarm. You can activate the system even if someone accidentally bumps into your vehicle.

Your transponder key’s alarm may go off at random if the battery is running low. Use your spare coded key if that happens Your primary key fob’s battery needs to be replaced if the problem goes away.

To avoid problems starting your truck, don’t keep heavy metal objects, electronic devices, or a second coded key on the same keyring as your primary key. When you’re attempting to start your car, avoid allowing anything like this to come into contact with the programmed key.

Even though they won’t harm the transponder, they may cause a short-term problem. Remove everything from your keyring except the programmed key and try starting the car again if you’re having trouble.


As a result, there are several possibilities for resetting the system if you experience a false alarm or your truck won’t start. Try pressing the alarm button on your key fob to deactivate the alarm and restart your system as a first step.

Anti-theft technology may have been activated for some other reason if that doesn’t work.

The door lock cylinder should be checked next to ensure it is not damaged. When the door is closed, it locks into the car’s frame, which contains the key. If the door appears not latching properly or is damaged, anti-theft technology may believe someone is attempting to pry it open.

Make sure no one has tried to open the door by pushing a screwdriver through the handle. The alarm may be going off because of a problem in this area. Contact your Ford dealer if the locking mechanism cylinder or door handle seems to have been damaged.

Verify that you’re pressing the correct key. When you’re in a hurry, it’s easy to pick up the wrong key and set off your truck’s anti-theft system, even if you think it’s obvious. Using a fake key will make the vehicle think you’re trying to get in.

How To Reset Anti Theft System Ford F150

Ford F150 Theft Light Blinking Won't Start: Causes & Fixes

You can program additional transponder keys to your vehicle yourself if you need more. In this way, your key and your vehicle’s remote entry system will work together to code the engine immobilizer and remote entry system.

A new transponder key can only be programmed if two previously programmed keys are available. The new key must be coded at a Ford service center if you don’t have two original coded keys in your possession. Follow these steps to set up the key:

  • Put the first previously coded key in the ignition to get the vehicle started. Keep the ignition on for at least three seconds and no more than ten seconds at the same time.
  • Remove the key from the ignition and turn it off. Re-enter the second coded key after 3 seconds and before 10 seconds.
  • Turn the ignition switch off to remove the second coded key. Insert the fresh, uncoded key into your car’s ignition within three seconds.
  • Keep the key in the on position for a minimum of six seconds after turning it on. Remove the new key from the ignition and restart the vehicle.

Your truck’s remote entry system and the engine can be started with the correct car key programming. The anti-theft indicator will flash for three seconds, then go out, during the programming process.

If the programming wasn’t done correctly, the anti-theft indicator light may flash rapidly and the key may not start your truck or continue to function in the remote entry system. If that doesn’t work, take the car to a Ford dealer to have a new key programmed. If that doesn’t work, try it again in another 20 seconds.

How To Disable Anti Theft On Ford F150

Anti-theft systems are well-known for causing annoyances. Anti-theft systems are often activated when there are no actual threats present, resulting in a false alarm, according to most people.

Key And Cylinder Examination

The first step would be to check the battery in the key fob. The false anti-theft alarm will likely go off if the device is dead and hasn’t disabled the system. If the battery runs out, get a new one.

Check the door lock cylinder as well. The lock cylinder would have been broken into if the theft attempt was genuine.

Using the wrong car key is another possibility. Some keys don’t have the right chip to start the engine. The answer to how to disable the anti-theft system is simple if you fix the underlying problems.

Starting Your Vehicle

Ford F150 Theft Light Blinking Won't Start: Causes & Fixes

The inability to start one’s vehicle is the bane of every motorist’s existence. Your engine may be locked if your anti-theft system kicks in. A nuisance, wouldn’t it be?

The anti-theft system must therefore be disabled. To begin, check your car’s dashboard for an anti-theft light, which will be either blue or red.

After the engine starts, insert your key and leave it there for 10-15 minutes.

As a final step, verify if the anti-theft light is blinking. After 2-3 minutes, turn the key again.

Make a fresh attempt at starting up; the ignition should work this time around. Always try again, no matter how many times you fail. The trick will likely work!

Combination Of Your Key And Vehicle’s Door Lock

Ford F150 Theft Light Blinking Won't Start: Causes & Fixes

To begin, turn the key in the driver’s side door lock. If you have a keyless system, use the physical key instead of the virtual one. To unlock the system, turn the key, but do not remove the keys from the ignition.

About 20-30 seconds later, remove the key from the keyhole.

Once the system determines that you are a legitimate user, the anti-theft protections will be disregarded. Alternating the key could also work. Now you can start the car.

It’s a sure thing! To lessen your risk of being a victim of auto theft, read up on some basic maintenance advice.

Final Thought

Theft is a serious problem, and it’s important to take measures to protect your vehicle. Fortunately, there are several ways to disable the anti-theft system on your Ford F150. By following our guide, you can rest assured that your vehicle is safe from thieves.


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