What are the functions of the four buttons on a car key?

[McJulian]

The four buttons on a car key are: the lock button, the start button (press twice quickly or hold down, some only require a single press, though this is rare), the unlock button, and the find-my-car button. Below is more detailed information: 1. Unlock Button: a. Pressing the unlock button once will only open the driver's side door; pressing it twice will unlock all four doors. This feature is particularly important for female drivers, as it can effectively prevent potential threats from entering the vehicle through the passenger or rear doors in quiet or remote parking areas. b. Remote window-opening function. During hot summers, when the car has been parked under the scorching sun, the interior temperature can become extremely high. Some car keys allow you to hold down the unlock button for a few seconds to open all four windows simultaneously, helping to release the hot air before entering. Some models may also open the sunroof. 2. Lock Button: This button is commonly used. Pressing it will lock all four doors. It also has a hidden feature: remote window-closing. If you realize after parking that you forgot to close the windows or sunroof, simply hold down the lock button to remotely close them. 3. Trunk Release Button: The car key often includes a trunk release button. If you're carrying shopping bags and need to open the trunk, you can hold down this button (some cars require pressing it twice) to automatically open the trunk. Some models even allow you to open the trunk by making a kicking motion under the rear bumper within a certain range. 4. Find-My-Car Button: Some car keys have a red button with a horn symbol or the word "Panic"—this is the find-my-car button. When pressed, the car's horn will sound, and the hazard lights will flash, making it easier to locate your vehicle in crowded parking areas.