From Autoblog
Anti-theft systems are designed to prevent your vehicle from being
stolen. These systems are constantly evolving. Essentially, they work
via an electrical circuit disconnecting to prevent power from flowing so
your car won't start or will die immediately. An anti-theft system may
also integrate a car alarm or it might just be an engine immobilizer.
It's possible that the anti-theft system in your car won't function
correctly at some point. This may be for many reasons including a dead
car battery that loses its key memory or a dead battery in your remote.
It could also be that your immobilizer chip is damaged in your key or
the car door lock is damaged. If your car's anti-theft system isn't
working correctly, you'll need to find a way to shut the system off so
your car will return to normal operation.
Method 1: Check your key and cylinder
Step
1: Check your key fob battery. A car's anti-theft system may activate
if your key fob battery is dead and hasn't disabled the system. Make
sure the battery is installed correctly in your key fob. If the battery
is correctly installed, replace it with a fresh battery and try again.
Step
2: Check your door lock cylinder. If your car has been damaged in an
attempt to steal it or break into it, the anti-theft system may have
been engaged. Check for damage to the lock cylinder itself or under the
door handle where would-be thieves may have punched through with a
screwdriver. If the lock is damaged, try using the passenger side
cylinder if your car has one. Note: While the driver's side door lock
is damaged, typically the passenger side won't be.
Step 3: Check
that you are using the proper key to start your car. Many cars have a
"valet" key or a door key that only performs certain functions such as
unlocking the doors. "Valet" keys are often distinguished by a "V" on
the key shaft or a different-colored key head. The key you are using may
not have the chip required to start your car.
Method 2: Turn the ignition on
If the anti-theft system has locked up your engine, you won't be able to start it. You'll have to disable it with these steps.
Step 1: Check for the anti-theft light. It's located on your dash and will have a blue or red light.
Step
2: Turn the ignition to the "on" position. Insert the key into the
ignition and turn it to the on position, which activates your
accessories but not the engine. Leave the key in position for about 10 –
15 minutes.
Step 3: Check the anti-theft light again. If it's no
longer blinking, turn the key back to the Off position and allow it to
set for a minute or two. This gives the system time to reset or you
won't be able to start your car.
Step 4: Start the engine.
Attempt to start your engine. If it still won't start, check to make
sure the battery hasn't been drained.
Step 5: Repeat the process. Try the process again to see if it will work.
Method 3: Use the key in your car door
Step
1: Insert your key in the lock on the door. Use the driver's side door
and the physical key even if your vehicle is equipped with a keyless
entry system.
Step 2: Turn the key. Turn the key to unlock your
car door, but don't release it. Hold the key in this position for 20 to
30 seconds. This lets the system know you have the correct key, and it
can allow you to bypass the alarm system. Some vehicles recognize the
key simply by turning the key back and forth in the door lock key
cylinder. Tip: Try turning the key both ways fully to disable the
anti-theft system.
Step 3: Try to start the engine. Remove the
key and try to start the engine. Be sure to leave the key cylinder in
the unlocked position. An anti-theft system that prevents your car from
running properly is a nuisance, and while you may be thankful for it in
the event of a crime, it is now causing you a great deal of
inconvenience, which these steps have hopefully helped you resolve.
If
your car still won't start, you should consult with a professional to
determine if there is another issue that is preventing your car from
starting.
