Everything You Need To Know About BMW Key Fobs

The list of BMW key fob functions keeps growing, from the simple remote unlock of the E46, through the keyless entry fob for vehicles with BMW Comfort Access, to the fully-featured touchscreen Display Key available for the latest models.

In that time, a lot has changed. Whether it's keeping your key charged, pairing it with your vehicle or keeping it safe, each generation of the fob has its own quirks. That means that if you've just upgraded from an old BMW and have a totally new fob, or you've just got a BMW key fob replacement, you could be wondering what it is and how it works.

We've looked into some of the most common questions people have about their BMW key fobs, and dug out the definitive answers!

Will a BMW start with a dead key fob?

If your BMW key fob's battery has run out, you won't be able to unlock your vehicle remotely or, if your BMW has Comfort Access, use keyless entry. However, you can still access and start your car manually.

First, to unlock your car's door, press and hold the key release button at the base of your remote fob and slide out the internal key blade. You can use this like a traditional key to unlock your vehicle. If the keyhole isn't visible on your vehicle's door, you'll find a small hole on the bottom of the handle. Insert the key blade in this hole and use it to pry off the trim panel to reveal the keyhole.

Once inside your vehicle, insert your remote key fob in the ignition slot or, if your car doesn't have one, hold it against the key markings on the side of the steering column. You'll then be able to start your BMW with the start/stop button on your vehicle's dashboard, even if your key fob is dead.

Is the BMW key fob rechargeable?

Depending on the version, the BMW remote key fob may come with a rechargeable battery, or it may have long-life battery that will need replacing periodically, perhaps once every few years depending on use.

In vehicles with a replaceable battery, you only need to pop off the fob's backplate and switch out the CR2450 or CR2032 coin cell. Non-rechargeable batteries are often found in key fobs with BMW keyless start.

Rechargeable batteries are found in some key fobs that need to be inserted into an ignition slot in your car, like in E60 and E90 vehicles without Comfort Access. In this case, the ignition slot doubles as a charger, topping up the battery while you drive.

Though a fob will last several years at least, all rechargeable batteries degrade over time. As rechargeable fobs are sealed with glue and have their batteries soldered in place, replacing the battery isn't an option. If your battery no longer performs, you'll need a replacement BMW key fob.

How do I replace the battery in my BMW key fob?

In fobs with a replaceable battery, replacing the battery is simple:

1. Hold the button at the base of the fob and slide out the internal key blade.
2. Find the small hole around the edge of the fob and use it to pry off the backplate.
3. Switch out the battery for an equivalent type, CR2450 or CR2032 depending on your fob.
4. Clip the backplate into place and return the internal key blade.

Older diamond-shaped keys and rechargeable fobs are not designed to have the battery replaced, and are sealed with glue. In this case, attempting to pry off the backplate may do damage to the fob.

How much is a BMW key replacement?

The cost of replacing your BMW key fob depends on which key fob version is required for your car, as well as the dealership you choose to shop with. 

Wherever you shop, for security reasons all replacement key fobs require proof of ownership, and need to come from BMW, having been prepared for your specific vehicle based on its VIN. Used fobs available on eBay or other platforms aren't suitable, and activating them would mean intentionally overriding BMW's security features intended to stop criminals accessing your vehicle with an unauthorized key.

To buy the key fob from a dealer you have to order it in the store and present all necessary documents, and then return once again to pick up your product.

Can you duplicate a key fob?

Your BMW can be paired with multiple key fobs simultaneously, making it easy for family members to each have their own fob. You can even add extra fobs by ordering a spare or replacement from BMW. However, each key fob is unique, and not a duplicate of any other.

The easiest place to see this is with driver profiles, which are associated with different key fobs. Each driver can have their own vehicle configuration, including seat position and radio presets, and unlocking their vehicle with their fob will automatically set the vehicle settings to match their preferences. Each fob will be associated with a unique profile.

To learn more about driver profiles and other hidden features of your BMW key fob, read our blog post.

How do I program a BMW key to start my car?

After buying a new key fob that has been prepared specifically for your vehicle, it is still necessary to activate your BMW key fob replacement. In recent vehicles:

1. Unlock your vehicle with your existing fob or key blade.
2. Hold the fob against the key marking on the side of the steering column, or insert in the ignition slot.
3. Hold the start/stop button until the no key warning disappears.
4. Release the start/stop button and press again to start your car.

In E-series vehicles with Comfort Access, you may also be required to code your vehicle to remove your existing key profile before you will be able to use the Comfort Access feature. It is necessary because E-series cars allow only for having two keys featuring Comfort Access in the memory of the car. So if you buy a new key, you’ll have to deactivate the previous one first and code your car to make the Comfort Access work.

Please note that this process cannot be done with a second-hand key or any key that has already been paired with a different vehicle. There is also a different key programming process for older BMWs

Can my BMW key be hacked?

As it's responsible for protecting your vehicle, your BMW's remote key fob was designed with security in mind. A sophisticated system means that your vehicle will only unlock when receiving a unique identifying signal from your fob, and the expected signal constantly changes. This makes it all but impossible for a third-party to hack your vehicle or clone your key.

In fact, most criminals won't even try to hack your key or break the security system. The more common threat is a third-party getting within range of your key fob, for example by sitting at the next table. In this case, it's possible to use a signal amplifier to broadcast the identifying signal from your key to an accomplice at your vehicle, who can then use the signal to access your BMW.

In these situations, some people prefer to keep their fob in signal-blocking pouch, which means a key fob power amplifier will not be able to detect your fob. The standard BMW key case does not include this feature, and is made only to protect your fob from scratches.

However, if you lose a key and worry that it will fall into wrong hands you can use the service of a key fob deactivation, which will block the key fob in the memory of the car to make it useless. Key fob deactivation can be done either by the dealer or our technicians.

Are BMW key fobs waterproof?

Standard BMW key fobs will generally be able to withstand typical, day-to-day moisture levels. Keeping it in your pocket on a rainy day, or even accidentally dropping it into a body of water, probably isn't going to cause any damage.

However, these fobs also come with a physical key blade inside the body of the fob. Pressing a button at the base of the fob lets you remove the key, which can be used to unlock your BMW's door. This removable key blade is sometimes known as a "surfer's key"; leave your fob out of sight inside your vehicle, and just take the internal key blade in situations when you're likely to worry about waterproofing.

As BMWs with Comfort Access are able to sense whether the fob is inside or outside the car, and will only allow keyless entry when the fob is outside the vehicle, this solution is even appropriate for owners of vehicles with Comfort Access.

Perhaps unexpectedly the BMW Display Key with touchscreen is a little less resistant. While the standard key fob can easily survive a trip in the washing machine, it's best to treat the Display Key as you would a smartphone — don't worry about rain, but keep it away from too much water.

What is BMW Display Key?

The Display Key is BMW's name for its most advanced fob, introduced for the G11 7 Series and now available for several premium models. The Display Key goes beyond what is normally expected from a key fob, featuring a full-color touchscreen.

As well as locking and unlocking your car, the Display Key lets you access vehicle information remotely. See whether the doors are locked, schedule when your air conditioning should come on and check your fuel level, all from a distance of almost 1000ft.

The stand-out feature, however, is support for remote control parking. With this, you can use your key fob as a remote control to inch your car forwards or backwards. It's perfect for tight spaces, when you don't want to shimmy alongside your car to and from the door. Learn more about the abundant features of a Display Key.

What is BMW Digital Key for iPhone

The future control of electronic devices undoubtedly leans towards mobile steering. And this is exactly what happens with Apple’s Digital Key launch. If you happen to have an iPhone with iOS 13 or iOS 14 and a BMW supported by the Operational System 7 you’ll be able to use the Digital Key functionality straight from your phone. 

The feature is enabled thanks to the NFC technology, which connects the iPhone to your car. This way you can unlock and drive your vehicle by tapping your phone, but also benefit from something pretty unconventional - the Apple CarKey sharing. This original option basically enables you to share the Digital Key with up to 5 drivers and place limitations on car settings, like top speed, accessible power or music volume. In unfortunate case of phone loss, you may disable the key for other drivers and revoke the access to the car via iCloud.