How to Solve the Issue When the Car Shows Locked and Won't Start?
3 Answers
Solutions for when the car shows locked and won't start: It may be due to the car's anti-theft lock being activated. The engine won't start because the key doesn't match—try using the spare key to start the car. The engine immobilizer system is an anti-theft mechanism installed on the engine, requiring the electronic chip to recognize a matching ID. The immobilizer is designed to prevent the car from being stolen by locking the engine if the doors are pried open. The key for an anti-theft engine contains a chip that verifies whether the engine ID matches. If the IDs don't match, the car will automatically lock and cannot be started or driven away. If the spare key doesn't work either, it could indicate a malfunction in the immobilizer system. Repairing the immobilizer is relatively complex, so it's advisable to promptly contact a 4S shop for inspection and repair.
I've encountered this situation before. Usually, a dead key fob battery is the simplest cause, especially when the remote locking works fine but the dashboard shows an anti-theft lock icon when starting. Don't rush to call a tow truck—first, try using the mechanical key to open the door, sit in the driver's seat, and press the key against the start button. Many cars have an emergency sensing function. If that doesn’t work, check other possibilities: Is there a strong interference source nearby, like a signal tower or medical equipment? Is the car battery drained, causing the anti-theft system to malfunction? It could even be a stuck steering column lock. Last time, I parked near a hospital entrance and got interference—just pushing the car a few meters away solved it. Don’t panic in such cases; rule out the simple issues first before heading to the repair shop to check the anti-theft control module.
This issue is actually quite common. I've encountered many cases during car repairs, mostly caused by the key chip triggering the anti-theft system. Try using the spare key to start the car. If it works, then the main key is confirmed to be damaged. If neither key works, you'll need to check if there are any aftermarket electronic devices inside the car causing signal interference, such as dash cams or GPS trackers. Another easily overlooked factor is metal stickers around the start button or keyhole, which can block signals. Recently, my neighbor's car had this issue due to a metal phone mount sticker causing system misjudgment. If you can't find the cause, you'll need to visit a dealership to read the fault codes with a diagnostic tool, and it might require re-pairing the keys.
