What Causes the Car Key Sensor to Fail in Cold Weather?
2 Answers
The reasons for the car key sensor failing in cold weather are: 1. The car battery is dead, causing the vehicle to fail to receive signals; 2. The remote key is out of battery or has insufficient power. The functions of a car key include: 1. Quickly locating the vehicle using the remote alarm feature; 2. Closing the windows after turning off the engine; 3. Automatically opening the trunk; 4. Selectively opening the driver's door. Types of car keys: 1. Mechanical keys; 2. Remote keys; 3. Touchscreen LCD keys; 4. Smart wristband keys. The working principle of a car key is: the key emits radio waves, which are received by the car antenna, and the electronic control unit (ECU) identifies the signal code, then the system's actuator performs the locking or unlocking action.
It was minus ten degrees that day, and I pressed my car key for a long time in the parking lot without any response—so frustrating! After consulting a professional friend, I learned that car keys are prone to malfunction in winter, mainly because the battery drains especially fast in low temperatures. Many electric car keys use button batteries that lose power when frozen, and insufficient power naturally leads to poor sensing. Additionally, electronic components contract in cold weather, causing contact points to disconnect, which prevents signals from being sent or received properly. At the time, I had to manually open the door with the key, but after replacing the battery, it worked much better. It's best to warm the key in your pocket beforehand or keep a spare key in the car to avoid delays in freezing weather. Regularly checking the battery is also important—don’t wait until a critical moment to find out it’s dead! This experience was a real lesson: warming up the key before driving in winter is definitely the way to go.
