My Toyota Prius Check Engine Light is on | What causes that?

August 25th, 2022 by

Why does a check engine light come on in my Toyota Prius? 

You may have noticed that your Prius has a light on its dashboard that indicates it has an issue. It could be anything from a loose gas cap to a potential problem with the engine or transmission. No matter what the check engine light means, there is something wrong with your car’s check engine system. Cars such as the Toyota Prius have check engine lights in order to alert you to any potential issues and ensure that you take care of those problems as soon as possible. If you see a check engine light come on for no apparent reason, you may wonder why this is happening to your vehicle and what can be done about it. Your answer may lie in one of the many causes below. 

When your Toyota Prius’s ECM (electronic control module aka the car’s computer), finds a problem, it turns on your check engine light. This orange light can be labeled “check engine” or could just be the picture of an engine. The code is then stored in the car’s memory and when you bring it into our Jacksonville dealership, we then assess the code to diagnose what is causing the error.  

What does the Prius check engine light mean? 

If you have a check engine light on your Prius but it seems to be running fine, it may be a sign that your fuel cap is not properly attached. A loose gas cap may cause the check engine light to come on. There could also be a problem with the throttle body or the fuel injector in your car. If there is a problem with these parts of your car, it could lead to a decrease in fuel economy and poor performance. Think of it like when your body gives you signal something is wrong – early diagnosis is the key to preventing something more serious from happening down the road.  

If the check engine light doesn’t go off when you turn off your car, this could be because something is wrong with your transmission or cruise control system. You could even notice a delay in how fast the car starts up. There may also be an issue with how quickly you can accelerate from low speeds on hills or drive up an incline. 

Will the check engine light reset itself in my Toyota Prius? 

It is possible for the check engine light in your Toyota Prius to reset itself, but it is not always the case. It is not like restarting a computer. For example, if a gas cap was loose and then re-attached correctly in your Prius, the issue is resolved and the check engine light will turn off. Or if you were doing a lot of stop and go driving, it could cause an issue with the catalytic converter in your Toyota Prius, which would also be resolved after this type of driving was done. 

Sometimes, the light will stay on indefinitely. If you do have this happen to your Prius, then you need to visit our certified Toyota mechanics here in Jacksonville. The check engine light may be caused by an issue with the car’s emissions system, the oxygen sensor, catalytic converter. An oxygen sensor could be causing short-term changes in fuel levels and temperatures that are causing the check engine light to come on.  

What else would cause the check engine light to come on in your Toyota Prius? 

  • Bad Spark Plugs 
  • Fuel and air metering systems problems 
  • Bad Battery 
  • Airbag warning lights 
  • Engine failure 
  • Computer circuit issues 
  • Fuel injection sensor issue 
  • Ignition system faults 
  • Faulty head gasket 
  • O2 Sensor 
  • Transmission issues 
  • Emissions controls issues 

How many miles can I drive my Toyota Prius after my check engine light comes on? 

The number of miles you can drive with a check engine light really depends on what the code signifies and unfortunately you won’t know that without getting your Prius checked out. Also, even though Florida doesn’t require it, many states require annual emissions inspection, and your Toyota Prius will not pass emissions if the check engine light comes on. So if you may be moving to another state, ensure your check engine light is not on. Bring it in to our Jacksonville dealership so we can diagnose the problem.  

How much does it cost to get a check engine in my Toyota Prius light fixed? 

Since there are many things that could be the culprit for why your check engine light is coming on it is impossible to say what the cost could be. For example, it could be a simple sensor that needs to replaced which could cost as little as $100. Of course, in rare cases it could be an issue with your transmission which could cost hundreds of dollars to repair.  

Is it safe to drive with a check engine light on in my Prius? 

You do have a window of time to get the check engine light diagnosed and fixed if it is NOT flashing. See below for what a flashing check engine light could mean. While a check engine light may not signal an eminent threat, it should not go undiagnosed. The light will go off when the system has been fixed and it no longer needs attention. If you notice a check engine light come on your Toyota Prius, it’s important to take note of what type of issue the light may be signaling. Some possible causes are: A malfunctioning sensor or sensor connector, engine or transmission failure, low coolant level, a bad battery or several other reasons.  

My Toyota Prius Check Engine Light is flashing – is it serious? 

A flashing check engine light is quite serious and should not be ignored. If this is not addressed soon, it could lead to costly repairs and could even be dangerous to drive.  The blinking light in your Toyota Prius means severe engine problems and if you continue driving your Prius, this can spread to the spark plug wires, catalytic converter, or ignition coils which can lead to an even more expensive car repair. 

While it can be frustrating, the check engine light on your Toyota Prius shouldn’t be ignored for very long if it comes on. A flashing check engine light should be taken even more seriously. Let our Jacksonville Toyota dealership fix it and have you on your way.  


Posted in Jax auto care