How to Change Battery in 2018 Tucson Key Fob Step by Step

We’ve all been there. You’re running late, arms full of groceries, and you press the button on your 2018 Hyundai Tucson key fob… and nothing happens. A second press, more frantic this time. Still nothing. That sinking feeling hits—the key fob battery is dead. Suddenly, the simple act of unlocking your car feels like a monumental task. Take a deep breath. I’ve been in that exact spot, and I’m here to tell you that changing the battery in your Tucson’s key fob is one of the easiest, most satisfying little fixes you can do yourself.

This isn’t a job for a mechanic or a dealership trip that costs you time and money. With a few minutes, a tiny tool, and a fresh battery, you can restore that magical “click” and get back to seamless entry and ignition. This guide isn’t just a set of instructions; it’s a walkthrough from someone who’s done it multiple times. I’ll share the little tricks and things to watch out for so you can do it confidently, without a hint of stress. Let’s get that key fob back in action.

Key Takeaways

• Use the correct battery type: A CR2032 battery is required for the 2018 Tucson key fob.
• Carefully pry open the fob: Use a small flat tool to separate the casing halves gently.
• Note the battery’s orientation: Observe how the old battery sits to insert the new one correctly.
• Test all functions after replacement: Press each button to ensure the key fob works properly.
• Avoid forcing the fob open: Excessive pressure can damage the internal plastic clips.
• Dispose of the old battery safely: Recycle it according to local regulations to protect the environment.
• Consult your owner’s manual if needed: It provides model-specific guidance for the key fob.

Everything You Need to Get Started

Before we dive into the physical process, let’s gather our supplies. One of the biggest frustrations is getting halfway through a project and realizing you’re missing a crucial piece. For this job, you don’t need a fancy toolbox. Here’s your simple checklist.

The Essential Tools and Parts

First, you need the right battery. The 2018 Tucson key fob almost universally uses a CR2032 3V coin cell battery. It’s a common, inexpensive battery you can find at any pharmacy, big-box store, or auto parts shop. I always recommend buying a name-brand battery (like Duracell, Energizer, or Panasonic) for longer life and more reliability. While you’re there, pick up a spare. Toss it in your glove box for the next time this happens—you’ll thank yourself later.

For tools, you have a few options. The absolute easiest tool to use is a small flathead screwdriver. The kind you’d find in a glasses repair kit is perfect. If you don’t have one, a sturdy butter knife, a dime, or even your fingernail can work in a pinch. The goal is to have something thin and strong enough to pry open the key fob casing without damaging it.

Finally, find a clean, well-lit workspace. A kitchen table or a desk with a towel laid down is ideal. Those tiny batteries have a habit of popping out and disappearing into carpet voids forever, so a flat, contrasting surface is your best defense.

A Quick Word on Safety

This is a very safe procedure, but there are two things to keep in mind. First, handle the new battery by the edges. The oils from your skin on the flat faces can, over time, reduce its effectiveness. Second, when you remove the old battery, take a second to note which side is facing up. This is your cheat sheet for installing the new one correctly. Getting this wrong is the most common mistake, but it’s easily avoided.

Step-by-Step: Opening Your 2018 Tucson Key Fob

This is the part that feels the most delicate. The key fob is designed to be durable, but you don’t want to force it. Follow these steps, and it will pop open smoothly.

Visual guide about How To Change Battery In 2018 Hyundai Tucson Key Fob

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Locating the Seam and Release Slot

Take your key fob and flip it over so the back (the side without the buttons) is facing you. Look closely at the edges. You’ll see a thin seam running all the way around the perimeter. On one of the shorter ends, usually near the metal key ring loop, you should see a small, shallow notch or slot. This is your entry point. On some models, it’s right where the silver key ring piece meets the black plastic. This slot is where you’ll insert your tool.

The Gentle Prying Technique

Insert the tip of your flathead screwdriver (or chosen tool) into that small slot. You don’t need to jam it in deep—just enough to get a grip. Now, apply gentle, twisting pressure. Think of it as a slight turning motion, not just prying straight up. You should hear and feel a soft click or pop as the first internal clip releases.

Once the first corner is free, carefully work your way around the fob. I like to gently slide my tool along the seam, applying light pressure every half-inch or so to release the subsequent clips. Go slowly. If you meet serious resistance, stop and check that you’ve fully released the clip before it. The casing should separate into two clean halves: the front (with the buttons and circuit board) and the back (a simple plastic cover).

Removing the Old Battery and Installing the New One

With the fob open, the heart of the operation is in front of you. This is a straightforward swap, but attention to detail is key.

Visual guide about How To Change Battery In 2018 Hyundai Tucson Key Fob

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Identifying and Removing the Depleted Battery

Look at the front half of the fob, the part holding the circuit board. The battery is housed in a circular, silver compartment right in the center. You’ll see the old CR2032 sitting there. Notice how it’s seated. In most 2018 Tucson fobs, the battery is held in by a small, thin metal bracket on one side. To remove it, you can gently slide a fingernail or the edge of your screwdriver under the bracket and lift it just enough to slide the battery out. Alternatively, you can often just push the battery from the side (under the bracket) and it will pivot up and out. The old battery should come out easily.

Placing the New CR2032 Correctly

This is the critical moment. Take your new CR2032 battery. Look at it—one side is completely flat and smooth (the positive side, often marked with a “+” and lots of tiny writing). The other side has a smaller, raised lip or notch (the negative side). Now, look at the empty battery slot in your key fob. You’ll see the metal contacts. The side with the smaller, springier contact is for the negative (notched) side of the battery. The flat, larger contact area is for the positive (flat) side.

My mantra is: “Flat side down, writing up.” In almost all cases, you want the flat, printed side of the new battery facing up toward you (and the buttons), and the notched side facing down onto the contacts. Carefully lower the new battery into the slot, ensuring it sits flush and snug under the retaining bracket. You should not have to force it.

Reassembling and Testing Your Key Fob

You’re on the home stretch! Now we just need to put everything back together and make sure our mission was a success.

Visual guide about How To Change Battery In 2018 Hyundai Tucson Key Fob

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Snapping the Case Back Together

Take the back cover of the key fob and align it with the front half. Make sure all the little plastic posts on one side fit into the corresponding holes on the other. Start by pressing the end opposite the key ring loop together first. Then, using your thumbs, apply firm, even pressure around the edges until you hear a series of satisfying clicks. Give it a gentle squeeze all the way around to ensure every clip has re-engaged. It should feel solid, with no gaps.

The Moment of Truth: Function Testing

Now for the fun part. Stand near your 2018 Tucson and press any button on the fob—lock, unlock, or panic. You should see a small LED light blink on the fob, and more importantly, your car should respond! Try it from a few different angles and distances. Everything should work just like it did when the fob was new.

If your Tucson has a push-button start, get inside and try starting the car. Even with a dead fob battery, the 2018 Tucson has a backup system. If your freshly changed fob doesn’t work to start the car, don’t panic. Simply hold the fob directly against the start button and then press. The key fob has a passive chip that communicates this way when the main battery is dead (or in our case, if there’s a very slight connection issue). This should start the car and confirm the installation is correct.

Troubleshooting and Pro Tips for Longevity

What if things don’t go perfectly? Or what if you want to avoid doing this again for as long as possible? Here are some insights from experience.

What to Do If Your Key Fob Still Doesn’t Work

First, don’t assume you broke it. The most likely culprit is an inverted battery. Pop the fob open again and double-check the battery orientation against the old one or the diagram in the slot. Is it seated fully under the bracket? Are the contacts clean? Wipe them gently with a dry cotton swab if they look dusty.

Second, test the new battery itself. It’s rare, but batteries can be dead on arrival. If you have a multimeter or can test the battery in another device, do so. If you bought a two-pack, try the other one.

Finally, ensure you’re using a CR2032 and not a similarly sized battery like a CR2025. They look almost identical but have slightly different thicknesses and capacities.

How to Make Your New Key Fob Battery Last Longer

A new battery should last 2-4 years, but your habits can extend that. Avoid leaving your key fob in extreme temperatures (like on a hot dashboard or in a freezing car overnight). Don’t store it right next to metal objects or other electronic devices, as this can cause the fob to “talk” more and drain the battery. And this is a big one: stop pressing the buttons when you’re nowhere near the car. Every time you press a button while your keys are on the kitchen counter, the fob is broadcasting a signal that goes unanswered, wasting energy.

Understanding Your Key Fob Battery Options

Not all CR2032 batteries are created equal. While any fresh battery will work, knowing the differences can help you make a smart choice at the store. Here’s a quick comparison.

Battery Specifications and Comparisons

The following table breaks down the key factors you might consider when purchasing a replacement battery. The “mAh” rating stands for milliampere-hour and indicates the battery’s capacity—a higher number generally means a longer lifespan.

For the vast majority of 2018 Tucson owners, a premium brand name battery hits the sweet spot of reliability, lifespan, and cost. I personally lean toward the “Long-Life” variants for the peace of mind, as the extra dollar or two is worth it for not having to think about it for years.

Wrapping Up: Empowerment in Your Pocket

And there you have it. What started as a moment of minor panic—a dead key fob leaving you locked out of convenience—is now a solved problem. Changing the battery in your 2018 Tucson key fob is a quintessential piece of easy, empowering car maintenance. It saves you a trip to the dealership, saves you money, and gives you that wonderful feeling of self-reliance.

You’ve learned not just the steps, but the little nuances: finding that release slot, the “flat side down” rule, and how to test everything thoroughly. Keep a spare CR2032 battery in your glove box or at home. You’ll be prepared for next time, and you might even be able to help out a friend or family member in the same bind. Now, go enjoy that satisfying click of your fully functional key fob. Your Tucson is ready when you are.