Toyota check engine light: Reasons and solutions

Mhenga November 5, 2022

2 27 7 minutes read

Table of Contents

Why is my Toyota check engine light on?

The check engine light never goes off: The onboard diagnostic system in your car has found a problem that has to be rectified. Even if your car might appear to be running smoothly, it’s best to take it in for service as soon as you can to avoid developing further problems.

Can I drive my Toyota with the check engine light on?

You should stop driving at this point and get your car checked out by a mechanic as soon as you can. When deciding whether to drive yourself or contact a tow truck to a local repair shop, use your best judgment.

What is the most common reason for check engine light?

The most frequent cause of check engine light illumination is the emissions/exhaust system. There can be a catalytic converter issue or an exhaust leak. Another sensor that is readily tripped or susceptible to failure is the mass airflow sensor (MAF).

What is wrong when check engine light comes on?

The gas cap is unsecured: Lock down the gas cap. Replace it with a new one if you’ve lost the old one. Oxygen sensor malfunction: You’ll need a replacement sensor, but first figure out which one is defective. Spark plugs could be faulty or fouled: Switch out the spark plugs.

Is the check engine light serious?

Yes, however, the check engine light is typically a sign that there is a significant issue with your car that needs to be fixed. The first step is to bring your automobile in to be evaluated by a qualified auto maintenance specialist.

Is it safe to drive your car with the check engine light on?

Check engine light, Toyota check engine light codes

Every Toyota check engine light has a meaning behind it. When you see that alarming light on your dashboard, your Toyota car is trying to tell you something

For Toyota check engine light:

P0133 – Heated Oxygen Sensor Circuit Slow Response Bank 1 Sensor 1

P0130 – Heated Oxygen Sensor Circuit – Bank 1 Sensor 1

P0125 – Insufficient Coolant Temperature for Closed Loop Fuel Control

P0121 – Throttle Pedal Sensor Switch “A” Circuit Range/Performance

P0116 – Engine Coolant Temperature Range/Performance

P0115 – Engine Coolant Temperature Circuit

P0110 – Intake Air Temperature Circuit

P0100 – Mass Air Flow Circuit

P0101 – Mass Air Flow Circuit Range/Performance

P0105 – Manifold Absolute Pressure Circuit

Toyota check engine light reset

To get you started on how to reset the engine light on your Toyota follow this guide carefully.

Turn the ignition on to start the vehicle. 2. Verify that the odometer is turned on and completely visible.
Turn off the ignition to stop the vehicle.
Push and hold the trip meter’s reset button.
Set the ignition to position I rather than start.
The odometer will show some dashes after finishing step 5.
Zeros will then emerge once the dashes have vanished.
Keep holding down the button until all the zeros are gone.

Toyota check engine light and trac off

Toyota VSC off sign is denoted by the Toyota TRAC OFF indicator.

If you push the TRAC OFF button, which is probably found on the left side of the steering wheel, you will see the TRAC OFF light appears on your Toyota dashboard. Whether you intentionally or unintentionally hit the button, it disables the traction control and/or vehicle stability control systems in your car. The VSC indicator has the word OFF and the image of a car sliding.

TRAC OFF indicator for Toyota
You might need to turn off TRAC or VSC if your Toyota becomes stuck in mud or snow. When you’re stuck, the systems could restrict the amount of power going from the engine to the wheels, which is not ideal. It may be simpler to rock your car out of the mud or snow if the systems are disabled. You only need to press the TRAC OFF button to turn it off. When your dashboard displays the TRAC OFF indicator, you will know you were successful. Just press the button once more to turn it back on.

Toyota check engine light blinking

The most common reason your Toyota check engine light is on

Toyota check engine light gas cap

This could be as simple as tightening or replacing your gas cap when your check engine light turns on. The check engine light may also be an indication of a significant issue that could seriously harm your engine and result in a costly repair bill. The Toyota check engine light may be illuminated or blink depending on your vehicle’s make and model. A constant glow normally denotes something less serious, but a check engine light that flashes suggests your car’s engine is seriously damaged and needs a quick repair. We strongly advise not driving your Toyota while the check engine light is flashing and setting up Toyota servicing right away. The most frequent causes of your Toyota check engine light appearing are listed below:

You must replace your mass airflow sensor or MAF. By detecting the volume of air entering the engine, the mass airflow sensor in your Toyota decides how much gasoline is necessary to run your engine effectively. The mass airflow sensor works with the engine management system to adapt to subtle changes like altitude. A faulty mass airflow sensor may be the cause of your Toyota’s difficulty starting, harsh idling, or sudden changes in the position of the accelerator pedal.
Your catalytic converter is faulty or deteriorating. The catalytic converter is a component of the exhaust system on your Toyota. The carbon monoxide produced during combustion is converted into carbon dioxide by the catalytic converter. Since neglected maintenance is frequently the root of catalytic converter problems, Nalley Toyota of Roswell includes a free multi-point examination with every Toyota service. If you have a catalytic converter problem and don’t fix it, your Toyota won’t pass an emissions test, will have poor engine performance, and will have a severe impact on your fuel efficiency. Additionally, your car may operate at a greater temperature, which might lead to additional issues from overheating.

For your Toyota, new spark plugs or plug wires are required. The component of your engine that ignites the air/fuel disparity in the combustion chamber of your car is the spark plugs. The pistons are moved by this explosion, which also powers the engine. The ignition coil’s spark delivers itself to the spark plugs through the spark plug wires. You will have poor performance and less power if your spark plugs or spark plug wires are worn out or defective. Your engine may have difficulties starting or running altogether in some rare circumstances. Worn ignition coils and O2 sensors can lead to blocked catalytic converters and more expensive repairs, as can worn spark plugs and plug wires.
Replace your O2 Sensor (also known as an oxygen sensor). The oxygen sensor, often known as an O2 sensor, gauges how much oxygen is present in your exhaust system. Fuel burns more quickly and your car will be less fuel-efficient if there is too much oxygen in the exhaust system.

It’s dead or the battery is low. Your Toyota’s battery is clearly visible. Your car won’t start, play the radio, illuminate the road in front of you, or charge your phone without a car battery. The batteries in today’s cars last a lot longer than they did decades ago, and they seldom ever need maintenance. The cost of a brand-new one varies depending on the Toyota model you drive, so be sure to browse our friendly servicing coupons and specials.

What will occur if I don’t replace your O2 sensor, then? In addition to lowering your miles per gallon, a bad sensor can harm your catalytic converter and the spark plugs in your Toyota. The O2 sensor transmits information to the car’s internal computer to identify the noble distinction between air and fuel that enters the engine’s cylinders. Additionally, a malfunctioning O2 sensor might make a car fail an emissions test.
Your Toyota is leaking vacuum. There is a vacuum system in every Toyota that serves a variety of purposes. By directing the vapors created as gasoline vaporizes inside the engine, the vacuum system also aids in lowering hazardous emissions. A vacuum leak may be to blame if you notice that your RPM is high when it is idle or fluctuates erratically. Vacuum hoses can dry out and crack over time, especially if they are subjected to excessive heat or cold.
any problems with accessories. If an aftermarket alarm, exhaust, or other component is not installed correctly, it might severely damage your Toyota. These aftermarket components and add-ons may deplete the battery, illuminate the check engine light, or even make it impossible to start the car. Bring your vehicle to Toyota if these problems sound new, and our team of qualified mechanics will check to see if your aftermarket parts were installed properly and aren’t posing any problems. It could cost a little more to purchase components, especially aftermarket parts and accessories, or to utilize OEM parts in the beginning, but doing so could prevent you from having to pay to have bad workmanship and damage brought on by sloppy installation work fixed.
Your gas cap is one of the most frequent and plentiful causes if it’s loose, broken, or missing. There are several uses for your Toyota’s gas cap. It seals the gasoline system, helps maintain pressure inside the fuel tank, and stops gas fumes from being emitted while you aren’t driving. What occurs if your fuel cap is damaged? You may lose fuel through evaporation if your gas cap is worn out or has a broken seal, which will need repeated trips to the pump. Fortunately, changing a gas cap is not expensive. Make sure the cap isn’t loose and that it’s still on the roof of your car or at the gasoline pump if your Toyota’s check engine light comes on right after you fill up with gas.

My final thoughts on Toyota check engine light and how to fix

The best solution for the Toyota check engine light is to follow the guide I have given you carefully. If this still doesn’t work and your engine light still tell you to check, watch the video below.