The check engine light on your dashboard is part of your car’s onboard diagnostics system (OBD-II), and it lights up when the car’s computer detects a problem that affects the engine, emissions system, or other paramount components of the car.
While it might be tempting to turn off the check engine light without fixing the issue that triggered the light, it’s important to understand that the light serves as a warning, therefore, ignoring it could lead to more huge problems down the road.
Moreover, if you’ve already resolved the issue (for example, you’ve tightened the gas cap or repaired a minor fault) and the light is still on, you can follow the methods explained below to reset it.
Simple Trick to Turn Off Check Engine Light
Here’s a simple trick you can use to turn off the check engine light:
Method 1: By Disconnecting the Battery
Disconnecting the battery is the most simplest and straightforward method to reset the check engine light. All you have to do is follow the steps below:
- Park the Car: Park the car in a safe location and turn off the ignition. You can also engage the parking brake.
- Open the Hood: Locate the hood release lever inside your car, usually near the driver’s seat. Pull the lever to open the hood, then secure it with the hood prop rod.
- Locate the Battery: The battery is usually found under the hood, often near the front of the engine compartment. It has two terminals: positive (+) and negative (-).
- Disconnect the Negative Terminal: Use a wrench to loosen the nut on the negative terminal (usually marked with a black cover or “-” sign). Carefully remove the negative cable from the battery terminal and set it aside, making sure it doesn’t touch any metal parts of the car.
- Wait for 15 – 30 Minutes: You must wait for 15 – 30 Minutes to give the car’s computer enough time to reset. During this period, the car’s stored data, including error codes that trigger the check engine light, will be cleared.
- Reconnect the Negative Terminal: After waiting, reconnect the negative cable to the battery terminal and tighten the nut with a wrench.
- Start the Car: Turn the ignition key to the “ON” position without starting the engine. Then start the engine. The check engine light should be off.
- Test Drive: Take your car for a short test drive to ensure everything is functioning properly. If the check engine light stays off, the issue may have been resolved. If it comes back on, it could indicate an unresolved or new problem.
Method 2: Using an OBD-II Scanner
An OBD-II scanner is a device that reads and clears diagnostic trouble codes from your car’s computer. You can use this method to turn off the check engine light as it is more precise and allows you to see the exact reason for the check engine light before turning it off.
All you have to do is follow the procedure below:
- Get an OBD-II Scanner: You can purchase an OBD-II scanner from an auto parts store or borrow one from some places that offer loaner tools.
- Locate the OBD-II Port: The OBD-II port is usually located under the dashboard, near the driver’s seat. It’s a 16-pin connector where the scanner plugs in.
- Plug in the Scanner: With the car off, plug the scanner into the OBD-II port. Turn on the ignition but don’t start the engine.
- Follow the Scanner Instructions: The scanner will power on and display instructions. Navigate the menu to read the trouble codes. These codes will provide you with specific information about what triggered the check engine light.
- Clear the Codes: If you’re confident that the issue has been fixed, you can use the scanner to clear the codes. This will reset the check engine light.
- Start the Car: After clearing the codes, start the car to see if the light stays off. If it does, you’re good to go. If it comes back on, there may be a deeper issue that needs to be addressed.
Why You Shouldn’t Ignore the Check Engine Light
The check engine light is your car’s way of telling you something needs attention. Hence, ignoring it could lead to:
- Reduced Fuel Efficiency: Problems like a faulty oxygen sensor can cause the engine to burn more fuel than necessary, costing you more money at the pump.
- Increased Emissions: Many issues that trigger the check engine light are related to the emissions system. Ignoring them could cause your car to emit more pollutants.
- Possible Engine Damage: Some issues, if left unchecked, could lead to severe engine damage, which is far more expensive to repair.
- Safety Concerns: In some cases, the check engine light could indicate a problem that compromises your safety, such as an issue with the transmission or brakes.
Conclusion
Disconnecting the battery for 15 – 30 minutes is the simplest trick to turn off the check engine light. However, you can also use an OBD-II scanner to clear the codes and turn off the lights.
If the check engine light comes back on after resetting, or if you’re unsure about the problem, it’s best to consult a mechanic. They can diagnose the issue accurately and make the necessary repairs to ensure your vehicle operates safely and efficiently.
