Toyota Smart Key System Malfunction (How to Fix & Prevent)
Toyota began implementing smart key systems in 2004. Initially, this function was only available in the Corolla and Highlander. Today, it’s an optional feature in most Toyota models.
Your Toyota smart key system, like any other computer-controlled technology within your car, could malfunction. If it does, you should be able to identify the problem, as well as understand how to reset it.
Knowing what’s causing the problem can save you a lot of time, money, and frustration in the long run. Keep reading to learn more about this issue, including what causes the error, how to fix it, and how to prevent it altogether.

The smart key system malfunction is one of many potential messages that can appear on your Toyota, along with a “charging system malfunction”, “headlight system malfunction”, and many more.
Although these messages tell you what component is affected, it doesn’t tell you what went wrong or how to fix it. That’s what we’ll cover today in regard to the smart key failure message.

Meaning of This Message
If you’re seeing a “smart key system malfunction” error on your dashboard, you’ll be wondering what this means and how it will impact your Toyota.
A smart key system malfunction means that your Toyota’s smart key is not working properly. You may be unable to start your car normally or use other smart key features.
You’ll see this error message in the middle of your vehicle’s display. This message may flash when you attempt to start your car.
Possible Causes
There are a few different causes for this error message, however, one specific scenario stands out.
Many people experienced a smart key system malfunction after parking their car overnight or for a few days. When attempting to start the vehicle, they see the smart key malfunction error message.
Oftentimes the cause for a smart key system malfunction is a dead car battery, which could be a result of:
- Electronics were accidentally left on overnight, such as the interior lights
- An old or bad car battery that cannot hold its charge, especially in cold weather
- An electronic glitch where the car keeps some functions running and drains the battery
If it’s not a dead car battery, you may be experiencing one of these other less common issues:
- The smart key battery has died and must be replaced
- A computer system malfunction
Let’s talk about fixing your smart key malfunction.
How to Fix
Now that you understand a few reasons why you might be experiencing a smart key malfunction, let’s talk about getting it fixed.
1. Jump-Start Your Vehicle
As we mentioned previously, many people who experienced this issue had a dead car battery. To fix a dead car battery, you’ll need to jump-start your car.
Watch the video below on how to jump-start a car or click here for written instructions.
Jump Start Your Car Without Another Vehicle
When using cables to jump-start your car, you’ll need another vehicle to give you the power.
In some emergency situations, you may be alone and unable to find another vehicle to jump your car.
Luckily, you can pick up a portable jump-starter so you never have to worry about your battery dying.
2. If Jump-Starting Your Vehicle Didn’t Work
If you’ve jump-started your car correctly but you’re still experiencing this malfunction, then there is something else going on. Perhaps the battery in your key fob is dead or experiencing a connectivity issue.
We’ve written a comprehensive article on deactivating your Toyota’s smart key so you can start the vehicle while the key is malfunctioning, or you can watch the video below.
If you’re still unable to start your vehicle, contact your local Toyota dealer or trusted mechanic.
Driving Without the Smart Key
Yes, it’s still possible to start your Toyota! This can provide you with a short-term solution for driving your car should you be unable to fix your smart key system malfunction.
To start your car without the smart key, start by unlocking your car door using the physical key hidden within the fob, then:
- If your Toyota less than 15 years old: Hold the key fob’s Toyota logo up to the “ENGINE START STOP” button
- If your Toyota is more than 15 years old: Press the deactivation switch on the dashboard below the steering wheel
Learn more about this process here.
Remember: If your battery is dead, you’ll need to jump-start the car before attempting to start the car!
Benefits of the Smart Key System
The Toyota smart key system is a very convenient feature. It allows you to unlock the doors without reaching for the key. You also won’t need to take the key out of your pocket to start your car.
Imagine if you’re out shopping alone and carrying a large, heavy load. Your smart key will save you the hassle of putting your items down, unlocking your vehicle, then picking them back up and loading them into your trunk. No one likes fumbling for their keys!
The feature also unlocks and starts your Toyota vehicle as long as you have the key on you. This is because your car can detect when you have the key in your possession. You won’t have to worry about getting the key out of your pocket or finding it in your purse. Simply push a button and drive!
Preventing Future Malfunctions
As we’ve mentioned earlier, there are several different possible scenarios that could cause this issue. Luckily, there are some precautions you can take to help reduce the likelihood of this happening again.
Here’s how to reduce the risk of a smart key system malfunction:
- Keep jumper cables (or a jump starter box) on hand in case your battery dies
- Be sure to turn off all electronics, such as interior lights, when you park your car for the night
- Keep extra key fob batteries on hand
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The Bottom Line
The smart key system has been a game-changer for many Toyota owners; however, some have experienced a malfunction with the system, especially after parking their car overnight or for a few days. Often, the cause of this malfunction is a dead battery, which will require you to jump-start your vehicle. If this doesn’t work, deactivating your Toyota’s smart key to start your vehicle may be a short-term solution.
The main thing is that you know how to identify, fix, and prevent a smart key system malfunction. By following the steps outlined within this article, your smart key will be up and running again in no time.