Will Disconnecting Battery Reset Check Engine Light?

Will Disconnecting Battery Reset Check Engine Light

A car’s battery supplies power to all the systems of a car and when the battery is disconnected, it automatically reboots all the systems in the vehicle.

When the battery is disconnected, it clears all the error/trouble codes that have been sent by various systems to the computer’s main system.

However, the question is, will disconnecting battery reset check engine light?

The check engine light might not reset even after disconnecting the battery if the fault that caused the light is yet to be fixed. Even if it clears the warning light, after few minutes of driving, it will come back. Therefore, disconnecting the battery can only reset the check engine light if the problem that caused the light is fixed.

If the check engine light was on because of something very serious, disconnecting the battery can make the situation even worse.

What is a Check Engine Light?

The check engine light is the most dreaded warning light that can come on in any car. Car owners always try to avoid doing anything that makes the check engine light come on.

This is because the check engine light coming on is a sign that something is wrong somewhere in the vehicle and what makes it worse is that the problem could be several things so you don’t exactly know what is wrong until you start checking.

Everybody always wants their vehicles to function optimally at all times because when something is faulty there’s a chance you’ll have to spend to get it fixed

The check engine light usually comes on when the car’s computer has been sent a message by the onboard diagnostic system about a malfunction somewhere in any one of the numerous systems.

When the check engine light comes on, the problem is either from the emission system, the car ignition system, the fuel system, or the exhaust system.

The check engine light doesn’t equal a severe engine problem, sometimes it’s a result of little things like a loosely covered fuel tank, a faulty sensor, or even a malfunctioning spark plug.

As reiterated earlier you never know where the problem is from until you start checking and you could find out that it’s a severe problem in the car’s system. It could signify an engine problem or a malfunction of the anti-lock braking system.

Ignoring the check light is a very dangerous act and can put everyone in the vehicle at risk because you can’t tell what exactly is wrong and how severe the problem is.

The best thing to do when you notice that the check light comes on is to park your car, do a quick checkup on the not-so-serious things and if you don’t find any fault, drive your car to a repair shop for a check-up.

Causes of Check Engine Light Warning.

The check engine light can come on for several different reasons, could be a minor or a major problem.

What went wrong can be something that’d cost you a lot of time and money before it gets fixed, or it could be something that you can just fix by yourself and continue driving to your destination.

As reiterated earlier, the check engine light is not specific to one thing there are a lot of things that could be wrong. Let’s start with the easy-to-fix.

1. Loosely Covered Fuel Tank

The check light can come on because of a loosely covered fuel tank because when the fuel tank is not properly covered the fuel system considers it an abnormality. So it sends a message to the main computer system which triggers the check light.

2. Spark Plug

The problem could also be from the spark plug so one of the first places you should check is the spark plug. You could just quickly try to clean the spark plug and fix it back to know if that’s what triggered the check light.

3. Faulty Oxygen Sensor

The oxygen sensor measures the amount of oxygen that hasn’t been burned and is left in the exhaust system of the car.

When the oxygen sensor is faulty it is not measuring the unburned oxygen which is considered an irregularity and it is then reported to the car’s main computer which causes the check engine light to come on.

4. Faulty Mass Airflow Sensor

The mass airflow sensor regulates the amount is air that mixes with the fuel to aid proper combustion. When the mass airflow sensor is bad, combustion is not done right because the air going in for combustion isn’t regulated.

So it sends a message to the main computer which generates a code that will allow the check engine light to come on.

5. Faulty Catalytic Converter

The catalytic converter is a very important and expensive part of the vehicle’s exhaust system. It converts the toxic air that is being released from the engine into the exhaust system into less toxic gases.

When it’s faulty, toxic air can get into the car which can be very dangerous and harmful to everyone in the car. This is why the exhaust system sends a message to the onboard system which triggers the check engine light to come on.

6. Alarm Installation

If the alarm of your car was just installed and the check light comes on, it could be that the alarm wasn’t properly installed or maybe the product that was gotten isn’t compatible with your vehicle.

Will Disconnecting Battery Reset Check Engine Light?

Disconnecting the battery may or may not reset the check engine light, it all depends on why the light came on.

If the check engine light came on as a result of a faulty or something even more serious, disconnecting the battery would do you no good.

The light may go off once you restart the car but after a while, the lights will come on again because the fault hasn’t been rectified and the affected system keeps generating trouble codes that turn the lights on.

Which Battery Terminal Do You Take Off to Reset the Check Engine Light?

While trying to reset the check engine light by resetting it, you should be careful about which one goes off first so that the systems can be properly reset.

The negative battery terminal which is usually colored black with a minus (-) sign on it should be taken off. The positive battery terminal which is usually red doesn’t have to be removed to reset the battery.

All you have to do is disconnect the negative terminal and reconnect it to reset the check engine light.

How Long Do You Disconnect Battery to Reset Check Engine Light?

After the negative terminal has been disconnected, you should wait for about 15-20 minutes so that the car’s systems can completely clear all the error codes before you reconnect the battery.

When the battery has finally been reconnected, the error codes would have cleared and the check engine light would have been restored.

Other Ways to Reset Check Engine Light

Asides from disconnecting the battery and waiting for the systems to reboot before reconnecting the battery, there are other ways by which the check engine light can be reset.

One of the other ways the check engine light can be reset is by using an OBD2 scanner and code reader to clear the trouble codes that have been generated by the car’s system.

You could also keep driving and wait till the engine check light goes off by itself.

The last method is by turning your engines off and on four times in a row. This also works sometimes in resetting the check engine light


Ultimately, the check engine light should not be ignored whenever it comes on and you should not try to reset it if you haven’t rectified the problem.