Prius Key Fob Not Working: The Way To Fix

The key fob for your Prius hybrid is an essential piece of technology that allows you to lock and unlock your vehicle, start the engine, and control various security features. However, there may be times when the key fob stops working, leaving you stranded and frustrated. 

Whether it’s due to a dead battery, a faulty signal, or a problem with the key fob itself, it’s important to understand the potential causes of a malfunctioning key fob and how to troubleshoot and fix the issue. 

In this article, we’ll explore common problems that can cause your Prius key fob to stop working, as well as solutions and tips for resolving the issue and getting back on the road.

Prius Key Fob Not Working- Possible Causes

Here are the possible causes of a Prius key fob not working, with some additional details for each:

1. Dead Battery

One of the most common reasons for a Prius key fob to stop working is a dead battery. The battery in a 2010 Prius is a CR2032 lithium coin cell, while a 2015 Toyota Prius hybrid uses a CR1632 battery. If the battery is dead, you can replace it with a new one. 

Instructions on how to replace the battery can be found in your Prius owner’s manual or by looking up a video tutorial online. However, if the battery is not the issue, it may be a weak or interrupted signal between the fob and the car.

2. Key Fob Programming Issues

Prius key fobs use a remote keyless system that communicates with the car’s security system through a smart key. If the authentication fails, it can cause the key fob to stop working. 

Another possible cause of a malfunctioning key fob is a programming issue. If the fob is not programmed correctly, it won’t be able to communicate with the car’s security system. 

If you have multiple key fobs for your Prius, they may need to be reprogrammed to work with the car’s security system. This is especially true if you recently got a new key fob and it isn’t working.

3. Physical Damage

Physical damage to the key fob can also cause it to stop working. If you have dropped your key fob or exposed it to water or extreme temperatures, it may be damaged. 

Additionally, if the key fob is damaged or broken, it may not be able to lock or unlock the doors or start the car. 

If your key fob is physically damaged, you may need to troubleshoot the issue to determine if it can be fixed or if you need to replace the key fob altogether.

Prius Key Fob Not Working After Battery Change

If your Prius key fob is not working after you have replaced the battery, it could be due to a few different reasons. 

First, make sure the battery was inserted correctly, and try again. If that doesn’t work, you may need to reset the key fob. 

Another potential issue could be that the key fob’s programming was lost when the battery was replaced, so it may need to be reprogrammed. 

If you are still experiencing issues, it may be time to seek professional help from a Toyota dealership or a qualified auto locksmith.

Prius Key Fob Not Working With New Battery

Replacing the battery in your Prius key fob should restore its functionality, but if it’s still not working even after the battery replacement, the problem may be due to a weak or interrupted signal between the fob and the car. Distance or interference from other devices could cause this issue. 

To resolve it, you can try standing closer to the car or keeping the key fob away from other electronic devices and metal objects.

If the issue persists, you may need to reset or reprogram the key fob or seek help from a Toyota dealership or an auto locksmith.

Replacing Prius’s Key Fob Battery Process

Here’s a step-by-step process for replacing the battery in your Prius key fob:

  1. Identify the type of battery your key fob needs

Typically, Prius key fobs require a CR2032 battery, but it’s always best to check your owner’s manual or contact a Toyota dealership to confirm the correct type of battery.

  1. Open the key fob

This can typically be done by pressing a button or sliding a switch on the side of the key fob.

  1. Remove the old battery

This can be done by gently prying it out of its compartment with a small tool, such as a flat-head screwdriver or a coin.

  1. Insert the new battery

Place the new battery into the compartment with the positive side facing up.

  1. Close the key fob

Line up the two halves of the key fob and snap them back together.

  1. Test the key fob

Press the buttons on the key fob to ensure that it’s working properly.

That’s it! Following these steps should allow you to replace the battery in your Prius key fob and restore its functionality.

How Do I Reset My Toyota Key Fob?

If your Toyota key fob is not working properly, you may need to reset it. The process for resetting a Toyota key fob can vary depending on the model and year of your vehicle, but it typically involves the following steps:

  1. Enter your vehicle and close all doors.
  1. Insert the key into the ignition and turn it to the “On” position.
  1. Press and release the “Lock” and “Unlock” buttons on the key fob at the same time.
  1. Hold down the “Lock” button for 2-3 seconds, then release it.
  1. Turn the key to the “Off” position, remove it from the ignition, and test the key fob to see if it’s working.

If the above steps do not work, you may need to refer to your owner’s manual or seek help from a Toyota dealership or auto locksmith.

Key Fob Resetting Cost

The cost of resetting a key fob can vary depending on several factors, including the make and model of your vehicle and the type of key fob you have. In general, the cost of resetting a key fob can range from $50 to $200 or more.

If you’re experiencing issues with your key fob and think it may need to be reset, it’s always best to start by consulting your owner’s manual or contacting a Toyota dealership for guidance. 

In some cases, you may be able to reset the key fob yourself using the steps outlined in the manual.

How Do You Start A Prius With A Dead Key Fob?

If your Prius key fob is dead and you’re unable to start your vehicle, there are a few options you can try.

First, you can try using the physical key that is built into the key fob to manually unlock the driver’s side door. Once inside, you can start the vehicle by holding the fob up to the power button on the dashboard.

If this doesn’t work, you can also try replacing the battery in the key fob or using a spare key fob if you have one available. If all else fails, you may need to contact a Toyota dealership or auto locksmith for assistance.


Can I reprogram my key fob myself?

It depends on the make and model of your vehicle, as well as the type of key fob you have. Some key fobs can be reprogrammed at home, while others require a professional.

Does key fob stop working if car dead?

If your car’s battery is dead, your key fob may not work. However, if your key fob battery is still functioning, you should still be able to use it to manually unlock your doors and start your vehicle.

How long does key fob battery last?

The lifespan of a key fob battery can vary depending on a number of factors, including the make and model of your vehicle, how frequently you use the key fob, and the type of battery that is installed. In general, most key fob batteries last between 2 to 4 years before needing to be replaced.

Final Thoughts

A malfunctioning key fob for your Prius can be a frustrating experience, but it doesn’t have to be a costly or time-consuming one. 

By understanding the potential causes and solutions for a non-working key fob, you can quickly and easily troubleshoot and fix the issue, saving time and money. 

Whether it’s replacing the battery, reprogramming the key fob, or using the manual key as a backup, it’s important to be prepared for any key fob issues that may arise. 

With the tips and information provided in this article, you can keep your Prius key fob working efficiently and reliably for years to come.

Ricardo Vaughn
Ricardo Vaughn

Vaughn is a seasoned off-roading expert and professional winch specialist. When he's not out on the trails, he shares his knowledge and experiences through his writing as a blog author in the off-roading and outdoor lifestyle space.

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