What are the functions of the BMW Blade Key?

[StAutumn]

BMW Blade Key has functions such as illumination, opening/closing the trunk, and locking/unlocking the vehicle. Diamond-shaped button: It has an illumination function. When pressed, the car lights will turn on. In dark places or when there are too many vehicles, it can help locate the car, serving as a vehicle-finding function. Trunk button: Press to open or close the trunk. If the car is equipped with an electric tailgate, long-pressing the trunk button can fully open or close the trunk. Lock and unlock buttons: Used to lock and unlock the doors, open and close the sunroof, and can also be set to unlock only the driver's side door.

[VonXavier]

I really like the design of BMW's blade key—great feel and super slim. Beyond basic lock/unlock functions, it unlocks when you grip the door handle as the key approaches, and auto-locks when you walk away, which is super convenient. The key can also remotely open the trunk, super handy when your hands are full. In higher-end models, it even remotely starts the car—perfect for pre-cooling or heating the cabin in extreme weather. That small silver logo on the back? It pops open for battery replacement, just be careful with the clips. Oh, and some versions let the key flip open the door handle cover with a button press—pretty slick.

[DiAdam]

I've been using this metal card key for three years, and the most obvious benefit is that it doesn't dig into my pocket. Holding down the unlock button opens all windows including the sunroof for ventilation, while holding the lock button closes them all – no need to rush downstairs on rainy days. Once when my arms were full, I just lightly swept my foot under the rear bumper to pop the trunk, a feature many don't know about. The blade key has memory pairing with the car, storing my seat position, AC settings, and mirror angles. Though phone unlocking is available now, the physical key still feels more reliable – though it does get hot when left in summer sun.

[StWalter]

The blade-style key looks trendy but offers practical features. When unlocking, the headlights and welcome lights illuminate, making it super convenient to locate your car at night. No worries if the battery dies—there's a hidden mechanical key head on the side of the key that can be pulled out to open the door. Once, I dropped my key in a snow pile for half an hour, picked it up, blew it off, and it still worked fine—decent water resistance. The number of buttons at the bottom varies slightly across different versions, but the core functions remain similar. To save battery, avoid placing it near your phone, as it can interfere with the signal and drain power. This key can also control the opening and closing of some roof accessories.

[SanRicardo]

This key is far more than just a door opener. As you approach the vehicle with it, the ambient lighting inside the door handles and the angel-eye daytime running lights gradually brighten, creating a full sense of ceremony. When parking in tight spots, it can remotely control the car to move forward or backward slowly by a few meters—way better than calling for a tow truck. The key's chip stores the last few dozen vehicle status records, even tracking how many times the car has been washed. The anti-theft features are meticulous too—if the key is away from the car for a certain period, the engine automatically shuts off. Having driven my friend's older model, I noticed the new blade key feels much heavier than the old plastic-shell version, with its metal casing dissipating heat quickly, keeping your hands warm in winter.

[DiRonan]

BMW owners should be quite familiar with this metal key fob. When the battery is low, the dashboard will give an early warning to replace the battery—just pop it open and swap in a new CR2035 battery. Some might think the display key looks cooler, but aside from being noticeably heavier, it also requires frequent charging. Don’t lose the number on the back of the blade key—it can save you a hefty sum when getting a replacement. If you’re lending your car temporarily but don’t want to grant full access, setting a speed limit is a hassle-free solution. Personally, I like adding a leather keyring to avoid scratching my phone screen with the metal casing.