What Causes Remote Key Failure?
2 Answers
The reasons for remote key failure include a dead battery or poor battery contact, requiring battery replacement; failure of the timing control module in the remote key, necessitating module replacement; or aging of the car's remote transmitter antenna, which requires inspection and repair at a service station. The primary function of a car remote key is to remotely lock and unlock the car doors. The working principle of a car's remote key involves the owner pressing a button on the key, which then sends a signal containing specific command information. The car's antenna receives this signal, and after authentication by the Body Control Module (BCM), an actuator performs the locking or unlocking action. Each remote key contains an electromagnetic coil that emits microwaves. The one-touch start button also has an electromagnetic coil to receive these microwaves and relay them to the vehicle's computer. The computer then verifies if the key is a match. If the verification is successful, the vehicle starts. Placing the remote key near the vehicle's internal sensor can also start the car. The sensor location varies by model, so it's advisable for owners to consult their vehicle's manual beforehand.
I've also experienced sudden key failure before, most commonly due to a dead key battery. Actually, key batteries typically need replacement every two to three years. You can just open the cover yourself and replace the coin cell battery - the model number is usually visible on the old battery. Another tricky issue is signal interference - I've had my key interfered with three times near bank ATMs, and high-voltage electrical boxes can cause it too. It's important to develop good habits: don't keep your car key and phone pressed together in your bag for long periods, especially with metal phone cases which are particularly prone to blocking signals. If your key fails on rainy days, there's an 80% chance it's short-circuited from water exposure - you need to immediately open it up and dry it. Once at the beach, my key fell in the sand and I had to clean the circuit board with alcohol wipes to revive it. If you don't replace the battery for too long, it might leak and corrode the circuits - in that case, you'll have to get a new key.
