DIY Toyota Corolla Check Engine Light Diagnosing Process

This post is sponsored by Reman Engine.

There’s no denying that it can be frustrating when your check engine light comes on, seemingly without reason. If your Toyota check engine light alert is currently on and you’d prefer to avoid a trip to the mechanic, you can do a few things to analyze the issue yourself. 

Taking the DIY route isn’t perfect for every situation, but there are plenty of times when a DIY Toyota Corolla check engine light diagnosis can save you both time and money. So, before you schedule your car for an automotive check-up, let’s take a closer look at why your engine light might be on and what you can do to clear it. 

Shutterstock Photo ID 1182779827 by Luca Lorenzelli

Common Reasons for a Check Engine Light Alert

The check engine light doesn’t always mean that your car is navigating toward certain doom. In most cases, however, the presence of a brightly lit check engine light means something is amiss within your vehicle, so here are a few potential issues you might want to consider. 

  • Loose or cracked gas cap;
  • Failing catalytic converter;
  • Faulty oxygen sensor;
  • Faulty mass air flow sensor;
  • Fouled spark plugs or spark plug wiring.

Of course, there are other reasons that a check engine light will come on, but these are some common ones, primarily in the Toyota Corolla, that can act as a trigger. It’s crucial to start the DIY diagnosing process by evaluating when your check engine light comes on and how long it stays on. Try to answer the following questions. 

  1. Does your Corolla check engine light only come on in certain driving conditions? What do you notice when it does come on?
  2. Is your check engine light on constantly? 
  3. Can you notice any performance issues with your vehicle? If so, what are they?
  4. If your check engine light comes on and blinks consistently as you drive, your vehicle could have a significant performance issue, and you should probably have it serviced. 

Answering these questions will help you to understand if you need professional service or not. If you don’t think a professional is necessary and believe your engine light alert results from a glitch or minor issue, you can learn how to reset the check engine light Toyota. 

Resetting the Check Engine Light on Your Toyota Corolla

Ensuring nothing is wrong with your Corolla before you reset the check engine light is essential. However, we understand that driving around with your engine maintenance alert beaming for no reason is irritating and distracting. So, if you’re confident that nothing major is going on, you can go ahead with the Toyota reset check engine light process. 

  1. First, turn off your used Toyota Corolla engine and get safety glasses and gloves. It’s always essential to utilize the proper safety equipment when working on a vehicle. 
  2. Next, you’ll work with your car battery, so locate it under the front hood. To reset the check engine light on your Corolla, you’ll need access to the negative terminal on the battery, which will have a black cap and a negative symbol.
  3. With the proper-sized wrench, loosen the nut holding the negative battery terminal in place and pull the negative connector from the battery. Again, ensure your vehicle is OFF before attempting this step. Keep the negative battery terminal disconnected for sixty seconds. 
  4. Finally, reconnect the negative cable and ensure that you tighten the negative terminal sufficiently. 

This process will reset your entire dashboard, including any active infotainment system, so be prepared to reconnect any necessary electronic devices. Once you’ve taken these steps, the check engine light in your Corolla should go off and stay off. 

Diagnosing Your Check Engine Light

While it’s not always advisable to diagnose the cause of your check engine light coming on, in some cases, it’s necessary. If you’re dealing with a glitch or a minor problem that doesn’t warrant attention, resetting your check engine light on your own won’t harm your vehicle, and it could save you a costly trip to the Toyota service center. 

It’s essential to have some car knowledge or consult with someone who does before you jump in and diagnose your check engine light on your own. Always put your safety and the safety of your passengers first, and if you can’t figure out the cause of your check engine light, or it’s progressing from staying on to blinking incessantly, it’s time to see a professional. 

This post is sponsored by Reman Engine.

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