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In today’s world, unlocking your car or starting the engine has never been easier. With a simple press of a button, the days of fumbling for traditional keys are behind us. Car key fobs are the modern solution that offer a blend of convenience, security, and technology. But how do these small, often overlooked devices work, and why are they so crucial in today’s automotive world? In this blog, we will dive into the mechanics of car key fobs, their benefits, and why you should understand their functionality.

The Evolution of the Car Key Fob

Car key fobs, as we know them today, are a far cry from the traditional metal keys that dominated the automotive world for centuries. The shift from traditional keys to key fobs began in the 1980s and 1990s, as automakers sought more efficient and secure ways to unlock vehicles and enable keyless entry.

The first remote keyless entry (RKE) systems were introduced to the market in the 1980s. These systems allowed car owners to unlock their doors remotely without inserting a physical key. Over time, the technology evolved further, incorporating additional functions like starting the engine, opening the trunk, and even controlling the vehicle’s security systems—all from a single device. Today, most new vehicles come equipped with key fobs, and many modern models include advanced features like proximity sensing and even remote start capabilities.

How Do Car Key Fobs Work?

Car key fobs operate on radio frequency identification (RFID) or infrared (IR) technology to communicate with the car’s locking system. The process is relatively simple but requires precise technology to ensure security and functionality.

Radio Frequency Communication (RF): When you press a button on your key fob, it sends out a low-frequency signal to the car's receiver. This signal contains encrypted information, such as the command to unlock the doors or start the engine. The receiver in the car decodes the signal and executes the command.

Encryption for Security: One of the key benefits of car key fobs is the security they offer. The signal transmitted by the fob is encrypted, making it difficult for hackers or thieves to intercept and clone the signal. In addition, many fobs are programmed with rolling codes, meaning the signal changes each time the fob is used, further reducing the risk of duplication.

Proximity Sensors and Keyless Entry: Modern key fobs often include proximity sensors, which allow the car to detect when the fob is nearby. This enables keyless entry systems that unlock your car automatically as you approach. The fob only needs to be within a certain range—often just a few feet—for the car to recognize it.

Battery-Powered: Key fobs rely on small batteries to function. Most key fobs use lithium coin cell batteries, which typically last between one and five years, depending on usage. The battery powers the transmitter, receiver, and any additional features (such as a display or remote start).

Why Are Car Key Fobs Essential?

In addition to their basic function of locking and unlocking a car, key fobs have become essential components for vehicle security and convenience. Below are several reasons why these devices are more than just an accessory:

1. Enhanced Security

As vehicle theft has evolved, so too has the need for better security measures. Traditional car keys are relatively easy to copy, especially for older models. In contrast, key fobs provide far superior protection due to their encrypted signals and rolling code technology. This makes them much harder to duplicate or hack.

Moreover, many key fobs are linked to sophisticated alarm systems. If an unauthorized attempt is made to start the vehicle without the fob’s signal, an alarm will sound, and the engine will not start. This extra layer of security significantly reduces the chances of vehicle theft.

2. Convenience and Ease of Use

The days of manually unlocking a car with a metal key are long gone. Key fobs offer unprecedented convenience. With a simple button press, you can lock or unlock your doors, open the trunk, and even start the engine without removing the fob from your pocket or bag. This hands-free operation makes accessing your vehicle faster and easier, especially when carrying groceries or dealing with inclement weather.

The proximity sensing technology also adds an extra layer of convenience, allowing you to unlock and start your car without needing to press any buttons—ideal for those busy days when you’re juggling multiple tasks.

3. Keyless Entry and Remote Start

One of the most exciting features of modern car key fobs is the keyless entry and remote start functionality. These features have revolutionized how people interact with their vehicles. Keyless entry allows you to enter your car simply by being in close proximity, while remote start lets you start the engine from a distance, often via a smartphone app or by pressing a button on the fob itself.

Remote start is particularly useful during the winter months. It allows you to start the car in advance, so the engine and cabin are warmed up before you even step inside. Similarly, in hot climates, remote start can be used to cool the cabin, making the car more comfortable when you enter.

Global Adoption and Future Trends

Car key fobs have become a global standard, with nearly all major automakers offering this feature in their vehicles. As more people embrace technology, the demand for even smarter key fobs continues to rise.

In the future, we are likely to see further advancements in key fob technology. For instance, some manufacturers are already exploring biometric security features, such as fingerprint or facial recognition, to enhance the security of key fobs even further. Additionally, smartphone integration is becoming more widespread, allowing car owners to use their phones as key fobs, eliminating the need for a physical device altogether.

While car key fobs have transformed the automotive landscape, they also raise new concerns, particularly regarding privacy and hacking risks. As technology advances, automakers and tech companies will need to stay ahead of potential security vulnerabilities to ensure that key fobs continue to serve as effective and secure tools for car owners.

Car key fobs are no longer just a convenience—they have become an essential part of modern car ownership. From enhanced security features to the convenience of keyless entry and remote start, key fobs offer a range of benefits that make them indispensable for drivers around the world. As technology continues to evolve, we can expect even more advanced features to be integrated into future key fobs, further improving both convenience and security.

Understanding how key fobs work and why they’re important is crucial for anyone who wants to make the most of their vehicle's technology. As we look to the future, it’s clear that key fobs will continue to play a central role in how we access and interact with our cars—an innovation that started with simple remote locking and has now become a vital aspect of our daily driving experience.

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How to Protect Your Car Key Fob from Relay Attacks

How to Protect Your Car Key Fob from Relay Attacks

Car theft has entered the digital age — and unfortunately, so have the thieves. As car manufacturers move toward keyless technology, a new type of threat has emerged: the relay attack. Unlike traditional break-ins, this high-tech method allows criminals to steal a vehicle without touching the keys — or even breaking a window. Imagine this: your car is parked safely outside your house. Your key fob is inside, hanging on a hook by the front door. You're fast asleep. But outside, two individuals with small electronic devices are working together. One stands near your front door, scanning for a signal from your key fob. The other waits by your car. Within seconds, your key’s signal is captured, extended, and transmitted to your car. It unlocks, starts, and drives away — and you might not notice until morning. This is not science fiction. It's called a relay attack , and it's one of the fastest-growing vehicle theft methods worldwide. Why Relay Attacks Are So Effective The key to this technique is exploiting the constant communication between your car and its fob. Most keyless entry systems are designed for convenience — you don’t even need to press a button. The car automatically detects the presence of the key fob and unlocks when you approach. This convenience is exactly what makes it vulnerable. Relay devices — which are cheap, portable, and easy to use — can mimic the signal and trick the car into thinking the key is nearby, even when it’s inside your home. Security experts have raised the alarm about this method for years, but many drivers still don’t realize how easily their vehicles can be accessed. In the UK alone, keyless car theft now accounts for more than 90% of vehicle thefts involving high-end models, according to the AA. And with the rise of online tutorials and black-market tools, the problem is growing globally. So, What Can You Do to Stay Safe? Fortunately, protecting your vehicle doesn’t require advanced tech or a huge investment — just awareness and a few smart habits. One of the most effective ways to block relay attacks is also the simplest: store your keys in a signal-blocking container . Often called a Faraday pouch or Faraday box, this lined case prevents radio signals from escaping. When your keys are stored inside, they can’t be scanned or cloned, no matter how close a thief gets to your home. Placement also matters. Many drivers leave their keys near the front door or on an entryway table — spots that are easy to access from outside. Moving your keys to the center of your home, an upper floor, or even a metal box can reduce signal exposure dramatically. Some newer key fobs allow you to manually disable the signal when it’s not in use. This feature is often hidden in the manual and rarely mentioned by dealers. Taking a moment to learn whether your key supports this — and how to activate it — can make a big difference. It’s also worth checking whether your vehicle’s software is up to date. Many automakers periodically release firmware updates that strengthen encryption or reduce signal range. In some cases, updates can even detect and block suspicious unlock attempts. And while it may seem old-fashioned, physical security still works . Devices like steering wheel locks or gear shift immobilisers can be powerful visual deterrents. Even if a thief manages to unlock your vehicle, the sight of a bulky lock inside may be enough to send them looking for an easier target. If you're looking for practical solutions beyond GPS , check out our blog: Do Car Keys Have GPS? What You Need to Know About Key Tracking . In summary, here are a few key takeaways to keep your keys and vehicle safer: Store your fob in a signal-blocking pouch or metal container Keep keys away from entry points like doors or windows Disable keyless signals if your fob supports it Update your car’s firmware regularly Use visible anti-theft devices as a deterrent Looking Ahead: Smarter Cars, Smarter Drivers Relay attacks are part of a larger trend — one where modern technology makes life more convenient, but also creates new risks. Just like we’ve learned to secure our phones and passwords, we now need to think about how we secure our vehicles. As carmakers explore more secure solutions — like Ultra Wideband (UWB) tech and biometric verification — drivers still need to take responsibility for their vehicle’s safety. The tools are already out there, and many of them cost less than a meal out. It’s not just about avoiding theft; it’s about peace of mind. So next time you get home, before tossing your keys on the hallway table, take a second to think: are they really safe there?

5 Reasons Why Your Car Remote Isn’t Working and How to Fix It

5 Reasons Why Your Car Remote Isn’t Working and How to Fix It

In an age where convenience is king, keyless entry systems have revolutionized how we interact with our vehicles. Gone are the days of fumbling for physical keys—today’s drivers rely heavily on the sleek, compact functionality of car remotes. However, what happens when this modern convenience fails you? Few things are more frustrating than standing beside your car, repeatedly pressing your remote, only to be met with silence. Understanding why your car remote isn’t working can save you from unnecessary panic, costly repairs, and inconvenient lockouts. This comprehensive guide explores the five most common reasons your remote may malfunction and offers in-depth, actionable solutions to get you back on the road quickly. 1. Battery Depletion: The Silent Saboteur The number one reason for car remote failure is, unsurprisingly, a dead or depleted battery. Though seemingly small, the battery inside your remote plays a crucial role in its operation. Most key fobs use lithium coin batteries (commonly CR2025 or CR2032), known for their durability and longevity. But even these reliable power sources don’t last forever. Factors contributing to faster battery depletion include: Frequent use (especially for remote start and lock/unlock functions) Extreme temperature exposure (both heat and cold reduce battery life) Long periods of inactivity (leading to gradual discharge) Solution: Replacing your key fob battery is a simple, cost-effective fix. Always consult your vehicle’s manual to identify the correct battery type. When replacing, ensure the new battery is seated correctly to avoid poor contact. Proactively changing the battery every 1-2 years, even before it’s fully drained, can prevent sudden failures. 2. Signal Interference: The Invisible Obstacle Key fobs communicate with your vehicle via radio frequencies. However, various external factors can interfere with this communication. Living in urban environments, parking in underground garages, or being near large electronic devices (such as cell towers, Wi-Fi routers, or even other vehicles) can disrupt the signal between your remote and car. Solution: If you suspect signal interference: Move closer to your vehicle or try unlocking it from a different angle. Step away from potential sources of interference like electronic devices or heavy machinery. Hold the key fob higher or away from your body to improve signal transmission. While occasional interference is common, if the problem persists across multiple locations, consider resetting or reprogramming your fob. 3. Desynchronization: Losing Connection Sometimes, your key fob may lose synchronization with your vehicle’s receiver—especially after events like a battery change or extended periods of non-use. When this happens, the fob and vehicle are essentially "speaking different languages," resulting in non-responsiveness. Solution: Check your vehicle's manual, as many manufacturers provide step-by-step instructions to manually re-sync the fob. Typically, this involves a sequence like inserting and turning the ignition key, pressing specific buttons, or opening and closing the doors in a set pattern. If manual reprogramming fails, you may need assistance from a dealership or certified locksmith equipped with the necessary diagnostic tools. 4. Physical Damage: The Wear and Tear Factor Remote key fobs, despite their solid appearance, are not invincible. Everyday handling—dropping the remote, spilling liquids, or even rough storage—can cause internal components to malfunction. Moisture exposure, in particular, is a key offender, leading to corrosion or short-circuiting of the circuitry inside. Solution: Inspect your remote regularly for: Visible cracks, chips, or signs of wear Sticky buttons or unresponsive keys Water damage indicators If damage is evident, replacing the remote may be your best bet. For minor issues, cleaning the interior components (after carefully opening the casing) with a soft cloth and isopropyl alcohol can sometimes restore functionality. Consider investing in a protective cover to prevent future damage. 5. Vehicle Receiver Issues: The Hidden Problem While the key fob often gets the blame, sometimes the issue lies within your vehicle’s receiver system. If the receiver—which detects and processes the signal from your remote—is malfunctioning, your remote will appear useless regardless of its condition. Solution: One telltale sign of a faulty receiver is if multiple remotes fail to operate the car. In this case, the problem is likely internal. Diagnosing and fixing receiver issues typically requires professional assistance, either from a dealership or an experienced automotive technician equipped with specialized diagnostic tools. Global Context: Keyless Challenges Worldwide The rise of keyless systems isn't limited to one region—it’s a global phenomenon. However, as technology advances, so do the challenges. For instance, key signal cloning and relay attacks have become prevalent, particularly in Europe and North America, prompting manufacturers to enhance security measures continually. Understanding the basics of how your key fob works and its vulnerabilities can help protect against both everyday failures and more sophisticated threats. Stay Ahead of the Problem Modern car remotes offer unmatched convenience, but when they fail, the disruption can be significant. Whether it’s a dead battery, signal interference, synchronization glitch, physical damage, or vehicle receiver issue, knowing how to identify and fix the problem puts you in control. Take proactive steps—replace batteries regularly, handle your remote with care, and familiarize yourself with your vehicle’s reprogramming process. A small investment of time today could save you from major headaches tomorrow. Stay informed. Stay prepared. And keep your car remote working seamlessly, wherever the road takes you.

The Impact of Artificial Intelligence on Automotive Innovation: A Glimpse into the Future of Driving

The Impact of Artificial Intelligence on Automotive Innovation: A Glimpse into the Future of Driving

The automotive industry is experiencing a transformative shift, and at the center of this revolution is artificial intelligence (AI). From the development of fully autonomous vehicles to enhancements in key systems, AI is changing how we drive, maintain our vehicles, and secure them. While these advancements promise increased efficiency and convenience, they also raise new questions, particularly regarding cost, accessibility, and how car owners will interact with their vehicles in the future. Let’s take a closer look at how AI is reshaping the automotive world and why it’s important for car owners to understand these changes. Smarter Cars, Smarter Keys Artificial intelligence isn’t just revolutionizing self-driving cars—it’s also transforming the traditional car key. What once required a physical key is now being replaced by more advanced, secure alternatives. With the rise of smart keys, biometric access, and mobile apps, car keys are becoming increasingly sophisticated. AI-powered keyless entry systems allow you to unlock and start your car without needing to take a physical key out of your pocket or bag. The car senses your presence and communicates wirelessly to grant access. Additionally, biometric keys such as fingerprint or facial recognition are gaining traction, ensuring that only authorized users can access the vehicle. These systems are nearly impossible to duplicate, offering an unparalleled level of security. While these innovations add layers of convenience, they also highlight the growing need for professional key replacement services to ensure your car's security isn’t compromised. Autonomous Vehicles: A Step Toward the Future The idea of self-driving cars has long been a futuristic concept, but AI is making it a reality. Although fully autonomous vehicles are not yet mainstream, the technology is evolving quickly. AI algorithms are able to process data from sensors, cameras, and radars in real-time, allowing the car to navigate without human input. While fully autonomous driving has the potential to reduce accidents caused by human error—responsible for over 90% of crashes today—there are still many challenges to overcome. Self-driving cars must be equipped with robust systems capable of handling emergencies and unpredictable situations, which are crucial for ensuring safety. Even if true autonomy is still a few years away, many modern vehicles already feature semi-autonomous capabilities, such as adaptive cruise control, automatic emergency braking, and automated parking. These features, powered by AI, offer significant improvements in driving safety and convenience. Predictive Maintenance: Preventing Problems Before They Happen Imagine a world where your car could tell you when it’s about to break down. With AI, this is becoming a reality. Predictive maintenance, powered by AI, is revolutionizing how we approach vehicle care. AI-driven systems can analyze your car’s performance in real-time, predicting when parts need servicing before they fail. Examples of Predictive Maintenance : Notifications for upcoming maintenance, such as oil changes or brake pad replacements. Alerts about issues like low tire pressure or a battery nearing its end. Suggestions for repairs based on your driving patterns, reducing the chances of unexpected breakdowns. By identifying potential issues before they become major problems, AI helps save you time and money, providing a smoother, more reliable driving experience. Enhanced Driving Experience AI is not only about improving vehicle performance but also enhancing your overall driving experience. Through smart technologies, driving has become more intuitive and enjoyable. Voice assistants, for example, allow you to control various functions hands-free, from adjusting climate settings to managing calls and navigation. AI also customizes your vehicle experience based on your preferences. Over time, AI learns your favorite seating positions, climate control settings, and even your regular routes, making every drive more comfortable. With AI-powered infotainment systems, you can enjoy real-time traffic updates, personalized music playlists, and even hands-free control over entertainment choices. These innovations make driving safer, more enjoyable, and tailored to your individual needs. Transforming Vehicle Security The introduction of AI in automotive security is setting new standards. As vehicles become increasingly connected, the potential for cyber threats rises. Fortunately, AI is being implemented to protect against these risks, offering peace of mind for car owners. AI-enhanced Security Features: Advanced Theft Protection : AI systems can detect unusual activities, like attempted break-ins, and alert you immediately via your smartphone. Geo-fencing : Some vehicles now allow you to create safe zones. If your car moves outside the designated area, you’ll receive an instant notification. Anti-Hacking Measures : As cars become more integrated with the internet, AI helps protect against cyberattacks, ensuring your vehicle's systems remain secure. These features not only protect your vehicle from theft but also provide you with more control over your car’s safety, no matter where you are. What This Means for Key Replacements As AI continues to evolve in the automotive industry, the process of replacing and programming car keys is becoming more complex. Advanced keys, such as those based on biometric authentication or smartphone applications, are more expensive to replace than traditional metal keys. Furthermore, these modern systems require specialized equipment and expertise to program properly. For car owners, it’s essential to stay informed about your vehicle’s key system. Always keep a spare key on hand and familiarize yourself with emergency unlocking features, so you're prepared if something goes wrong. Challenges of AI in Cars While the benefits of AI in automotive innovation are clear, there are also some challenges to consider. AI can drive up the cost of manufacturing and repairs, and adapting to new features can sometimes be overwhelming for drivers. High Costs : Implementing AI technologies in vehicles can increase both the initial price and the cost of repairs. Learning Curve : Some drivers may find it difficult to adapt to new, AI-driven features, especially if they are not technologically inclined. Dependence on Connectivity : Many AI-powered systems require an internet connection, which can be problematic in remote areas or locations with poor service. Being aware of these challenges will help you navigate the evolving automotive landscape and make informed decisions about your car’s technology. Embracing the Future of Driving Artificial intelligence is rapidly transforming the automotive industry, changing everything from how we drive to how we secure and maintain our vehicles. For car owners, these innovations bring immense convenience and enhanced security. But they also require a deeper understanding of the systems that power your car, from keyless entry to semi-autonomous driving features. As AI continues to develop, staying informed will help you make the best decisions for your lifestyle and budget. Whether you’re exploring new key technologies or considering a fully autonomous vehicle, the future of driving is undeniably shaped by AI—and it’s already here.

What’s the Difference Between a Key Fob, Smart Key, and Proximity Key?

What’s the Difference Between a Key Fob, Smart Key, and Proximity Key?

Over the past two decades, vehicle security and convenience have evolved dramatically. Traditional metal keys have steadily given way to a range of more advanced systems that offer not only better protection but also more comfort for the everyday driver. Among the most commonly used terms in today’s automotive world are key fob , smart key , and proximity key . While often used interchangeably, these are not identical technologies. Each represents a step forward in how drivers interact with their cars, and understanding the differences between them is essential—especially when replacing, repairing, or purchasing new key components. In this article, we’ll explore each key type in detail, highlight what sets them apart, and offer practical insights to help you identify which type you own—and what that means for functionality, replacement options, and compatibility. Key Fob: The Foundation of Remote Access A key fob , in the modern context, refers to a remote control device that allows users to perform basic functions such as locking or unlocking the car doors. The word "fob" originally described a decorative accessory on a keychain, but it has evolved to refer specifically to these electronic remotes. Most key fobs use radio frequency (RF) signals to communicate with the vehicle. When you press a button on the fob, it sends a coded signal to a receiver inside the car, instructing it to lock, unlock, open the trunk, or activate the panic alarm. Some key fobs also include a physical key blade that can be used manually if the battery is dead or if the remote functionality fails. Key fobs became standard in the early 2000s and are now found in nearly every modern car. They represent the bridge between the traditional mechanical key and more advanced systems. While they don’t offer hands-free operation or engine-starting capabilities by default, they introduced a level of convenience that significantly improved the driving experience at the time of their launch. Smart Key: Hands-Free, High-Tech, Highly Secure The smart key builds on the foundation of the key fob but adds a major element of sophistication: hands-free access and ignition . With a smart key, you no longer need to press buttons to enter or start your vehicle. Instead, the key communicates continuously with the vehicle via low-frequency antennas and encrypted signals . As long as the key is within a certain range—often in your pocket or handbag—the vehicle automatically detects it and allows for keyless entry and push-button start. In many smart key systems, simply touching the door handle unlocks the vehicle. Once inside, starting the car requires nothing more than pressing a button on the dashboard. Some smart keys even store personalized settings, such as seat position or mirror alignment, offering a more tailored driving experience for each registered user. Originally reserved for luxury vehicles, smart keys have become increasingly common across all vehicle classes. Brands like Lexus, Mercedes-Benz, and BMW were early adopters, but today you’ll find smart keys in many Hyundai, Kia, Toyota, Nissan, and Volkswagen models. They offer both convenience and enhanced security thanks to rolling code encryption, which helps prevent signal interception and unauthorized vehicle access. Proximity Key: The Functional Twin of the Smart Key The term proximity key is often used synonymously with smart key, and in many cases, it functions in the same way. A proximity key allows the car to detect when the key is nearby—typically within one to three feet—and respond accordingly. You can unlock the car simply by approaching or touching the handle, and engine start is enabled through a button as long as the key remains inside the cabin. However, while all smart keys are proximity-based, not all proximity systems include the full feature set of a smart key. In some vehicles, the proximity key may lack advanced personalization or remote app integration, but the core functionality— hands-free locking, unlocking, and push-to-start capability —remains intact. The term “proximity key” is more commonly used in owner manuals or by manufacturers in Europe and Asia, while “smart key” has become the marketing standard in North America. Regardless of the terminology, the underlying technology is largely the same, relying on short-range radio waves, signal encryption, and two-way authentication between the key and the car. Breaking Down the Differences To simplify the distinctions between these three key types, it’s helpful to focus on user experience and technical capability. A traditional key fob requires active input—pressing a button to unlock the doors—whereas smart and proximity keys allow for passive, automatic operation. Additionally, the integration of engine start buttons, memory features, and enhanced security protocols tends to be exclusive to smart and proximity systems. Another notable difference lies in design and construction . Key fobs often have visible mechanical blades and rubber buttons, while smart keys are usually more compact, feature fewer or no physical buttons, and hide the emergency key blade inside the unit. Understanding this can help when shopping for replacement shells, batteries, or full units. Identifying Your Key Type Not sure which key your car uses? You’re not alone. Here's how to tell: If you must press a button on your key to unlock the doors and start the engine with a physical ignition slot, you’re likely using a key fob . If your car unlocks automatically when you approach and starts with a dashboard button —without ever removing the key from your pocket—you have a smart key or proximity key . If your car allows for keyless entry but still requires button pressing on the remote , it's most likely a standard key fob with added convenience features. Why Knowing the Difference Matters Understanding what type of key you use is crucial when you’re purchasing replacement components. A smart key cannot be replaced by a basic key fob, as it contains far more complex electronics and vehicle-specific programming. Likewise, replacing a proximity key requires knowing the exact frequency, chip type, and compatibility with your vehicle’s immobilizer system. At mr-key.com , we help car owners find exactly what they need—whether it’s a replacement key shell, a fresh battery, or a full remote unit with electronics and transponder chip included. With detailed listings sorted by make, model, and key type, it’s easy to identify the correct product and avoid costly dealership programming fees. As automotive technology continues to evolve, so does the way we access and operate our vehicles. Whether you're using a classic key fob, a cutting-edge smart key, or a proximity-based system, each offers a different balance of convenience, security, and technical complexity. Recognizing the key you use—and understanding how it works—not only makes you a more informed vehicle owner but also helps you take better care of your key system. When the time comes for a replacement or upgrade, you’ll be prepared to make the right choice quickly and confidently. For high-quality, vehicle-specific replacement parts, visit mr-key.com . From fob covers and CR2032 batteries to complete electronic keys and blades, we’ve got everything you need to keep your key performing like new.

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