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How to Change Battery in Prius Key | Easy Key Solution for Your Toyota in 2021

This guide on how to change battery in Prius key does not only show you a straightforward process to replace your key’s battery. It also entails all you should know about your Prius key fob.

Changing a fob’s battery is technical and also inevitable maintenance for your key fob’s efficient functionality, so you must learn the right steps to get this done without inflicting any damage to the fob.

Contents show

What is the Smart Key?

A smart key is basically a key designed to access its relating vehicle electronically. It is part of a fob that allows you to operate your vehicle, with the fob in your pocket or at a specified distance. You can find this key on most modern cars.

How Do Smart Keys Work?

Even if the key is placed in a cup holder, it will still work in locking and unlocking or starting the car due to the antennas present in the vehicle’s body and because of the radio pulse generator found in the key.

The radio signals of the key link with the car to carry out these convenient tasks. Most smart key systems work when a sensor is active or when a door-knob is pressed.

Some smart keys system will loosen the immobilizer found in your car and activate the car’s ignition without using a key in the ignition, provided you are with the key. Some use a starter button for this operation, while others use a twist on their ignition switch.

What Do I Do if My Prius Key Battery Dies?

A dead Prius key does not stop you from operating your vehicle. You have to push a button at the side of your fob to reveal your metal key. You can use the key to open your car door.

Place your dead fob near your start button and press the button to start your Prius. If your car didn’t respond, use the fob to press the start button.

However, if you can replace the battery immediately it would save you this stress.

Do You Have to Reprogram a Key after Replacing the Battery?

The key does not need to be reprogrammed after changing the battery. The key fob will still work after the old battery is changed, but it’s the receiver that needs to be reprogrammed if it does not.

What Size Battery Does the Key Take?

Most keys use CR-2032 or CR2025 3-volt batteries. The key’s battery is usually written in their manual and is mainly sold in any dealership or electronic shop.

The numbers found in the battery normally indicates the size in height and diameter. The CR2023 being the most popular type of battery used for most keys, it is 3,2mm tall and 20mm wide.

Although most key fob needs one or more lithium-ion and a 3-volt coin battery. When requesting a key, most times, you have to consider the model, make, and year of your car production to get the best fit for your vehicle. But the most common types of batteries found are 2032, 1616, 1632, and 2025.

If you are using a RAM, Dodge, Jeep, your fob battery’s size will either be CR2450 or CR2032.

Installation Materials Required?

To replace your battery, you will need a new set of batteries or batteries, a screwdriver, and a prying tool, a flat end screwdriver.

How Do You Open the Key?

To open your key, all you need is a screwdriver. Use the small flat head of your screwdriver to open up your smart key carefully.

To prevent breaking of your key shell, try opening from a different location surrounding the fob. This process only takes a few minutes.

Look for a small crack on the keypad. Some key fobs have openings on top, where the keychain and keypad connect, which is a wide spot. Insert the screwdriver and gently pry it open to avoid breaking your key.

Step by Step Installation Guide on How To Change Battery In Prius Key

01. Take off the Metal Ignition Key

Press the button at the bottom or side of your key fob to detach the fob’s metal key.

02. Pry the Fob

Use a flat object or other convenient prying tools into the opening created from detaching the metal key, and carefully open your fob.

03. Take Out the Circuit Board

When the fob is opened, remove the circuit board, usually green in color. You will have to use a screwdriver to take off the screws holding the board firm.

04. Replace the Battery

Behind the circuit board lies the battery you need to change. Gently remove the battery and place in the new ones.

05. Reassemble Your Fob

Couple your fob back properly using a reverse process and fix back the metal key. If done correctly, you have your key fob working perfectly normally as possible.

Approximate Cost of the Service/Setup

To set up a new battery for a key fob, you need about $50-$100, depending on the car model or the dealership. Toyota dealership charges $13 to install a key’s battery for you. While some dealerships will do this for free, others will charge you $3 per hour.

Common FAQs Related to Toyota Smart Key

01. What’s the Cheapest Way to Get a New Smart Key Fob for a 2007 Toyota Prius? Can I use a Generic Fob?

Smart key fobs are unique devices that use special codes specific to their designed vehicle. This key lets you operate your vehicle, including starting, driving, locking, and unlocking the vehicle. Different vehicles are designed with special smart keys. So you cannot have two cars having identical keys.

For generic fob, it uses a much less number of codes than the factory-designed fobs. Usually, all vehicles designed with a factory programmed smart key, so even after you get a generic fob, you have to program the fob to your vehicle.

If you don’t know how to program your fob, make sure you go to your dealership. Giving a random person to help you out can be quite risky as your key can be duplicated.

02. How Can I Open My Toyota Prius Key Fob?

Gently slide off the small door key fixed at your fob’s side. With a prying tool, you can pry open your fob through the seam. You have to maintain caution while prying. If you do it properly, then your Prius key fob will open.

03. How Long Can I Drive My Car Without a Wireless Key Fob?

Now, if your wireless key fob is somewhere around in your car and you forgot to take the key with you, but the key was just close enough to start your vehicle and run-off.

Usually, your vehicle alerts you when it can’t find the key fob. However, it lets you drive the car for as long as your journey demands without going off, except until you are out of gas. But when you turn off the car, you will be stuck.

Then you will have to get your fob, or you can program a new one if you can.

04. What Will Happen to My Keyless Car in Motion if My Key Fob Stops Transmitting Signals?

When your vehicle scans for the key and cannot communicate the key, it immediately sounds an alarm to alert you, the driver. This can happen when your key fob is far away from your car or when the fob’s battery dies. In either of these cases, your car won’t receive signals from the fob.

If you are not low on gas, the car will continue to function until you replace the battery or get the fob close by. You shouldn’t turn off the vehicle until the fob is fully functional or within reach.

05. With my keyless engine on, and I’ve got my key. If someone enters my car and drive off without the key, what will happen to my car?

Usually, it depends on the vehicle model you drive. In some vehicles, If you use the remote start in the vehicle, it won’t start the engine until you have the key fob inside the vehicle, and then you press your pedal while pushing the start button.

So, with these types of vehicles, it will be difficult for anyone without the key fob to drive the car.

But with other models that don’t need to have the key fob in the car, anyone can drive off with the vehicle as long as the fob is within range, and the car won’t stop until it is out of fuel.

06. How far away can I use my key fob to lock my car?

You should be able to lock your car with your fob from about a hundred feet. But with your vehicle’s app, you can operate your car from a much farther distance, even when you are not in the state.

07. How long does a key battery last on regular operating?

With normal use for most cars, battery life usually lasts 3-4 years. Hence, to keep your key fob functional, you have to replace the battery at that interval.

Some older products are known to last longer than newer ones; an example is the basic Ford produced within 2000 – 2009, whose key fob battery last for over five years.

08. What is the cost of replacing a quality Toyota smart key?

Depending on the model, replacing a smart key can cost $250-$700 and even more. Toyota has developed a new key product to protect key replacement through its Toyota financial services, making smart key replacement less expensive or stressful.

Some Common Problems and Solutions about Toyota Car Key

When you have an issue with your key fob, it usually is as a result of these highlighted factors

Wrong placement of your key

This happens when you forget your key inside your car and locked the entire door. The worst part is when you have the spare key trapped inside too.

Loss of communication with your car’s ECU (Engine Control Unit)

When you insert your key into your car, it transmits a special code to the engine control unit, and when the system interprets this code, it puts it on your engine.

The ECU can malfunction at some point and fail to recognize the code transmitted by your key. So it won’t allow your engine to start.

Faulty key

Of course, smart keys are durable and more expensive than standard keys, but they are also prone to damages, especially when kept carelessly around.

When you fail to care for your key, you might start noticing malfunctions, until eventually, you can’t use the key for the vehicle.

Missing key

This problem isn’t like others, there’s no damage to your key, but then you cannot find it. It can be stolen or misplaced; whichever the case may be, you won’t be able to go into your vehicle, and if you do enter, you can’t start the engine.

Solutions related to Toyota Key

Reprogram the key

This will work when your key can’t communicate with your vehicle’s ECU. If you can’t reprogram the key correctly, you should go to your dealership for help so your vehicle will start receiving and transmitting codes again.

Protect your key

Most of the problems with a car key are when the key is not kept properly. Mishandling your key will only end up damaging the key. Ensure you store your key in a safe place and change the battery of your key fob when due.

Key replacement

In situations where you can’t locate your keys, spares included, or your keys are severely damaged, you are left with the option of replacing them.

Maintenance

To maintain your car key fob, ensure you change your fob’s battery at the recommended date, place the key in clean and dry areas, and avoid throwing it around.

If the fob is faulty, take it to the dealership for servicing, and do not hit the fob against hard objects; handle the fob with care.

Do’s and Don’ts

Things you need to note when dealing with car keys

Don’t hide your spare keys in an open area in your car

It seems like a good thought to keep your spare key in your car, but you need smart. It’s better to keep the key in a magnetic box fixed to the exterior part of your car, which would be easy to reach. For instance, you lock yourself out. It will be easy getting into your vehicle or operating your car.

If you keep it in a safe place, it would be easy for thieves to spot it. So you need to place the box in a secure spot, difficult to find.

Do keep spares away from your vehicle

It’s advisable to store your spare keys outside your vehicle. You can keep it in your house or wallet. You can easily reach it if need be. This is a more secure option, and with this, you shouldn’t worry about getting locked outside your vehicle. Trusting a family member with your spare key is also another good alternative.

Don’t use a non-certified locksmith

Hiring a non-certified locksmith to operate your car when having a key issue or locked out of your car can be very dangerous. Your lock can end up getting damaged, and you might be charged higher than normal rates. Always go for a certified locksmith.

Do hire professionals

Resolving a car key issue can be quite complicating and might require some certain technicalities. If you do not understand how to change battery in Prius key or other models, attempting to fix the issue yourself can worsen the situation.

So hiring a professional is a wise decision with reliable services guaranteed.

Final Words

If you still hold any uncertainties on this subject, you can always get to us to help resolve them. However, as long as you heed this guide, you shouldn’t have any issue with your key fob.

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