
Engine anti-theft system fails to connect with the key. When the key malfunctions, it will display authentication failure. The vehicle's engine electronic anti-theft system has an anti-theft converter embedded in the car key. When the key is inserted into the ignition switch lock cylinder and turned to the "ON" position, the electronic anti-theft ECU communicates with the key via radio frequency. Here is additional information: Engine anti-theft: Engine anti-theft authentication failure means the car key is not detected. Most of these situations occur because the car key has no power or there is an issue with the receiving module. When encountering this situation, you should check your car key.


