What are the reasons for engine authentication failure?
2 Answers
There are several possible reasons for engine authentication failure: 1. The internal chip of the key is not matched/locked. 2. Fault in the anti-theft read coil. 3. Communication failure between the anti-theft coil and the anti-theft control unit. 4. Internal failure of the anti-theft control unit/communication failure with the engine control unit/lack of matching between them. 5. Electromagnetic wave interference, etc. The solutions for engine authentication failure are as follows: 1. Open the door and sit in the driver's seat, take out the car remote key, and place it on the one-touch start button for more than 30 seconds. 2. While keeping the key on the one-touch start button, press the unlock button on the remote key. 3. Press the lock button and trunk button a few more times. 4. If the engine system authentication failure alarm still cannot be resolved after several attempts, it is recommended to take the car to a repair shop for inspection.
A few days ago, while I was driving, the engine suddenly displayed an authentication failure and wouldn't start, which really puzzled me. Experience tells me that the most common cause is a depleted key battery. My remote key had been used for almost five years without a battery replacement, and it started normally after installing a new battery. Apart from battery issues, the anti-theft system might also give false alarms, such as significant signal interference or a humid environment causing poor sensor contact. Programming errors after vehicle modifications are another common factor—like my friend who had issues after replacing the lock cylinder without proper system pairing. I recommend trying the spare key first; if that doesn’t solve the problem, then take it to a repair shop to check the ignition module or reprogram the key. Developing a habit of replacing the key battery every two years can effectively prevent such failures.
