Why Does the Car Key Get Hot After Being Pulled Out?

[Elrond]

This is a normal phenomenon. The heating of the car key is directly proportional to sun exposure. The car ignition lock is made of metal, and the hotter the sun, the more heat it absorbs. The temperature inside a closed car under direct sunlight can reach over 80 degrees Celsius. The thin car key inserted into the lock hole will quickly heat up, hence the car key becomes hot. The light above the car keyhole: There is a light above the car keyhole, and it's not an LED. With a lower color temperature, it emits a warmer light. After prolonged exposure, the car key heats up. Magnetic field changes: For car keys with anti-theft chips, after the key turns the ignition switch, the factory-installed electronic anti-theft system automatically detects it. The magnetic coil inside the ignition switch may generate heat due to changes in the magnetic field, causing the car key to heat up. This is a normal phenomenon. The excessive current passing through the ignition switch (except for the high current of the starter motor, which does not pass through the intermediate relay for safe conversion).