How To Turn Off The ‘Check Engine’ Light?


Check engine light comes on when there is one or more than one problem in your car. This is done by the Engine Management System (EMS) of your car.

A Universal On-Board Diagnostics (OBD) system monitors all the critical components of a modern car. From engine to clutch and from brakes to suspension, everything is monitored by an OBD.

Thus, any kind of off-sync between the car components will lead to the ‘check engine’ light being turned on. Ideally, the light should turn off itself after the issue is resolved.

But what if the ‘Check Engine’ light doesn’t turn off?

4 Ways To Turn-Off The Check Engine Light

1. Disconnect The Battery

Battery disconnection technique is a conventional way of resetting your car’s check engine light in some cars.

Remove the car battery cables and disconnect the positive power cable to the vehicle battery. Press and hold the car horn for about 30 seconds to drain any electricity from the vehicle’s capacitor.

After leaving the battery disconnected for at least 15 minutes, reconnect all battery terminals and make sure they are well tightened to avoid any possible sparking, and then switch on your car.

This will clear the emissions data from the vehicle memory as well as the readiness flag data. Wait for a few minutes and the check engine light will be turned off.

2. Use Scanner

One of the easiest ways to reset the check engine light is to use a scanner. This scanner is plugged into the ODB2 DLC (On-Board Diagnostics Generation Two Data Link Connector) port.

First, turn off the vehicle. Then, plug your OBD2 scan tool into the DLC, and turn the key to the “On” position. 

And after the connection is established between the computer and car, press the ‘read’ button scanner so it can check all activities going on.

Activate the function ‘clear DTCs’ or ‘erase codes’, which may take a few seconds to complete. Also, read the documentation of that particular tool or app for specific instructions.

Once the problem is solved it is recommended to turn the ignition off and on again. This is the easiest yet efficient method to turn off the ‘check engine’ light.

3. Solve The Problem

‘Check Engine’ could be turned on due to the following problems in your car:

A. Loose Gas Cap - The cap is a crucial part of a car’s fuel-delivery system. It notably prevents gasoline fumes from leaving the fuel tank. Thus, if the check engine light suddenly turns on, checking the gas cap should be your first priority.

B. Spark Plug Issue - A foul spark plug can cause engine misfire and hesitation under heavy acceleration. It is one of the most common problems that trigger the check engine light.

C. Sensor Failure - Modern cars have multiple sensors to keep everything synchronized and make your ride comfortable. Failure in even any one of them will lead to the engine light being turned on.

D. Bad Catalytic Converter - A catalytic converter fails due to a combination of problems in spark plugs, wires, and oxygen sensors. It converts pollutant gases into less harmful ones, like carbon dioxide. Thus, if the check engine light is being turned on due to this, then it can be a really bad sign! 

There can be dozens of more issues like these that can trigger the check engine light. If you want to know in detail as to that, why your check engine light is on? Here’s why!

Thus, fixing the core problem should be your priority. After the problem is being solved, lights will automatically turn off. go away.

4. Let It Go By Itself

Sometimes, you do not need to do all these things. The light might be turned on due to a minor bug or some tiny issue. Also, the ECU will take some time to fully run through its cycle of checks, and could take weeks to clear fault codes.

If this issue is minor like a mass airflow or O2 sensor failure, it may fix automatically, and the light may turn off.

Driving it normally for a few days will solve the issue.

Get An Expert Opinion

DIY methods are not always successful. That is why you need to take the help of professionals to tackle such problems.

Check engine light is a critical thing and thus should never be ignored or handled without care. Get a thorough auto repair in New Hope from A&G Customs.

All technicians are certified and have years of experience. Just give a call to 215 669 3072 and get your queries cleared.