Immobilizer / security light
A car outline with a key or a padlock, often flashing.
GENERALLY OK TO PROCEED WITH CAUTION
Book it in when you can · Amber means get it checked
What it means
A slow blink after you lock the car is normal — the immobilizer is armed. A problem is when the light stays on, or flashes as you try to start, and the engine will not fire because the car does not recognize the key.
What to try
Use the spare key if you have one, or hold the fob against the start button or ignition as your owner’s manual describes — a dead fob battery is a common cause. If it still will not start, our Car Won’t Start guide covers the no-start path.
Common causes
A weak fob battery, a damaged key, or a fault in the immobilizer antenna or module.
Warning-light symbols and meanings vary by vehicle — always check your owner’s manual. This is general guidance based on what the light indicates, not a physical inspection, and a light on its own never names a failed part.
Related Driver Help
Related warning lights
Want to know what is causing the warning?
Auto Star can read the codes, inspect the vehicle, and find the underlying cause before recommending any repairs — you see what we find and approve the work first.