How to Reset the Engine Light on a Car

What is the Engine Light?

The engine light is a dashboard warning light that illuminates when the engine control module (ECM) detects a problem with the engine or its emissions control systems. The engine light can be triggered by a variety of issues, including:

Loose or disconnected gas cap
Faulty oxygen sensor
Catalytic converter problems
Evaporative emissions system leaks
Engine misfires

Why Reset the Engine Light?

The engine light is designed to alert you to potential problems with your car, but it can also be a nuisance if it comes on for a minor issue. Resetting the engine light can be helpful if:

The issue that caused the engine light to come on has been fixed.
The engine light is on intermittently or for no apparent reason.
You want to sell your car and want to clear any outstanding engine codes.

How to Reset the Engine Light

Method 1: Disconnect the Battery

Put on safety glasses and gloves.
Locate the battery in your car. It is usually located under the hood, in the front of the car.
Disconnect the negative battery terminal. This is usually the black terminal with a minus sign (-) on it.
Wait 30 seconds.
Reconnect the negative battery terminal.

Method 2: Use an OBDII Scanner

Purchase an OBDII scanner. These scanners are available at most auto parts stores.
Locate the OBDII port in your car. It is usually located under the dashboard, near the steering wheel.
Plug the OBDII scanner into the OBDII port.
Follow the instructions on the scanner to reset the engine light.

Method 3: Use a Code Reader

Purchase a code reader. These readers are also available at most auto parts stores.
Locate the OBDII port in your car. It is usually located under the dashboard, near the steering wheel.
Plug the code reader into the OBDII port.
Follow the instructions on the code reader to reset the engine light.

Tips for Resetting the Engine Light

Make sure the issue that caused the engine light to come on has been fixed before resetting the light.
If the engine light comes back on after you have reset it, there may be a more serious problem that needs to be addressed.
If you are not comfortable resetting the engine light yourself, you can take your car to a mechanic to have it done.