Hyundai Ioniq Key Fob Not Working: Fixed

The most likely reason your Hyundai Ioniq key fob does not work is that the battery in the key fob is running low. Other possible causes include dirt clogging the key, a short circuit in the fuse box, or your E.V. not being charged sufficiently. If you have this problem, try changing the battery in your key fob.

But before doing that, remember that there’s a proximity limit for the fob to work with your Hyundai Ioniq. So it may not necessarily be a technical issue. 

Ideally, you need to be between 28 and 40 inches from the door handle for auto-unlock to work.

Now, if the key fob doesn’t work even with repeated pressing, then it’s most likely the battery of the fob. 

So, you can use another fob, replace the battery, or use the mechanical key.

And there is a proper way to handle these to avoid further unlocking complications for your vehicle.

So I encourage you to read till the end. In the rest of this post, I will show you the various workarounds for when your Hyundai Ioniq key fob refuses to work and how to fix it in a breeze.

6 Fixes for Hyundai Ioniq Key Fob Not Working

First, pages 5-13 of the Hyundai Ioniq owner’s manual specify what you can do to your key fob battery in the event of a malfunction. Here:

But before you pull out the battery, you want to consider a few no-brainer solutions to see if that resolves the problem. 

Considering the following fixes will also help diagnose the root cause of your key not working and how to solve it.

Check for Debris on The Key Fob.

Before you suspect your vehicle, examine the key itself. Elements as trivial as dirt can cause the Hyundai Ioniq key to not work correctly when clogged. 

So consider using a small brush to clean it, especially around the spaces between the buttons, and see if that works.

Change the Faulty Battery

Generally, the Hyundai Ioniq key fob battery has a lifespan of 3–4 years before it goes out.

The key fob battery could be faulty, which is a common issue, especially if your Ioniq is old or second-hand. 

Once you’ve determined that the battery is dead or damaged, you can manually open the doors and replace the battery. 

Here’s how:

Step 1: To replace the battery, first press the small dot on the button side of your fob

Step 2: Remove the mechanical key and press down on the slot on the right-hand side with a small screwdriver. Ensure the fob faces the button side up while you do this. This allows the fob case to open in half.

Step 3: You will be able to see the battery now. Remove it and carefully insert a new one. (the CR2032 battery for Ioniq key fob is available in auto part stores or online)

P.S.: Do not touch the face of the battery as you try to install it into the fob

Step 4: Click the casing back together and reinsert the mechanical key

Low battery capacity

Is your car battery fully charged? If not, it could be a possible reason you are having problems with the key fob not working. 

Meanwhile, expect a longer charging time if you use an old Ioniq model

Also, when charging your vehicle, ensure you’re using the correct charger cable and plug, as this guarantees better power output and safety while charging the battery pack of your Ioniq.

In addition, there could be a short circuit in the fuse box under your hood, which can cause the key not to work. Remove the fuse and reinsert it to see if it works.

Unlock the Car Mechanically.

This would be the last resort if none of the fixes above worked. Even with a dead key fob battery, you can start your car. 

A holder is located in the center of the vehicle, hidden inside the center console or glove compartment, as long as your car model has a Smart Key.

So first press the small circle at one end of the button side of your fob to release the mechanical key, and then lever it towards you.

Now locate the door’s handle and bend it. You will see a small rectangular hole where you can insert the mechanical key.

Meanwhile, your vehicle’s alarm will go off once you unlock the car with the mechanical key. 

The key fob is supposed to immobilize the alarm, but you must bear the noise.

How do you start a Hyundai Ioniq with a dead key fob?

When you finally get into your Ioniq vehicle with a dead key fob, how do you start it?

Now, if you try to press the start button, as we usually would, you will get a message on the display system asking you to press the start/stop button with the key fob.

And so, you use the top of your key fob to press and hold the start/stop button for a few seconds while pressing your brake, and then the vehicle starts.

The advantage here is that the Ioniq 5 prompts you on what to do when you can’t start it with the key fob.

If this doesn’t work, I recommend you refer to your vehicle’s operational manual for the exact location of key fob placement to start the vehicle because it may vary depending on the Ioniq model.

In summary

The bottom line is that many cases of the Hyundai Ioniq key fob not working have been linked to a dead battery in the key fob or a software glitch.

While the key has been made challenging to open, replacing the faulty battery is the only way to get it working.

You can get an oil change at the dealership and let them sort it out, but if you insist on DIY, the above article will help you swap the batteries without breaking the key fob.

Good luck.