How to Reset the Check Engine Light on GMC Sierra in 5 Easy Steps

Most vehicles today feature the malfunction indicator lamp, commonly known as the check engine light. It notifies you about any potential problems with your car or truck.

If you own a GMC Sierra, you must have noticed the check engine light turning on due to emission system problems most of the time. Honestly speaking it is a smart move to learn how to reset the check engine light on GMC Sierra, because you don’t know when need be.

Any mechanical failure, fuel system abnormality, or sensor problem may result in such situations. In addition, the OnStar Communication System or any other similar system may alert you by flashing the indicator lamp about a potential problem.

How to reset the check engine light on GMC Sierra


Can I reset the check engine light myself?

You can inspect the check engine light on your own. Here are the steps to help you reset.

  1. Locate the fuse box.
  2. Remove the check engine light fuse.
  3. Start the car and idle it for a couple of minutes.
  4. Turn off the vehicle.
  5. Replace the fuse.
  6. Restart the car.
  7. If the check engine light does not flash, there’s no problem.
  8. If the check engine light flashes, take your car to a mechanic for a deeper check of the vehicle.

How to reset the check engine light on GMC sierra? (Step-By-Step Guide)

It’s not a difficult task to learn how to reset the check engine light on GMC Sierra, and it can be accomplished with the following methods.

Let’s get to those.

How to reset the check engine light on GMC sierra (step by step guide)

Use a scan tool

You can use an OBD (On-Board Diagnostics) scanner tool to reset the check engine lights. Please follow the given steps.

Use a scan tool
  • Borrow an OBD scanner. Owning an OBD scanner can be costly, and you don’t use it daily. So it’s better to borrow.
    • Protip: If your vehicle model dates back to before the 1990s, it won’t feature any OBD ports under the dashboard. Even if it has, it may be an OBD-I port instead of an OBD-II port. In such a case, you may have to use a different scanner.
  • Locate the port under the steering assembly and plug the scanner there. Your vehicle’s manual may be helpful now if you cannot locate the port. The OBD port comprises two rows of 16 tiny openings for pins. The appearance is similar to that of a VGA port on old computers.
  • Insert the key into the ignition and turn on the vehicle, but don’t fire it now. Once the display lights flash on, turn off all other accessories, such as the radio and others that restart when you turn on the car. Locate the “read” button on the scanner and wait for the codes to appear on the OBD screen. The code is a combination of numbers and letters. Note all the codes to understand what they indicate and accordingly repair your vehicle.
    • Protip: A few scanners explain the codes. If not, you can always check in your owner’s manual or on the Internet.
  • Tap on the “erase/clear” button on the scanner. Turn off the ignition key. Erasing or clearing the codes turns off the check engine lights. Again turn on the car to receive a “no code” message on the scanner. Turn off the vehicle and disconnect the scanner.

However, just because the codes aren’t flashing on the dashboard doesn’t mean the problem has been fixed. If you notice the check engine lights flashing later on, take your vehicle to a mechanic to get it repaired by a professional.

Disconnect the battery

Disconnect the battery
  1. Locate your car’s battery and remove the -ve cable. You may have to use a wrench to do that. You may find the wire secured with a black cap and a minus sign. When the battery in the vehicle is disconnected, the codes from the radio memory and other onboard components are erased.
  2. Free up the capacitor of any remaining electricity by draining it out. You can likewise do that by pressing and holding the horn for half a minute. Or you can switch on the vehicle’s lights for a moment. Both the lights nor the horn won’t work due to the power-off status of the vehicle. However, it will help to empty the capacity by draining out the remaining electricity.
  3. Let go for 15 minutes, and then reconnect the battery. Disconnecting the battery for a couple of minutes completely resets the vehicle system once you reconnect the battery. Connect the -ve cable back to the battery terminal and secure it with its cap.
  4. Disconnecting the battery helps reset the check engine light.

Check the owner’s manual for specific instructions

As soon as any malfunction reporting lights flash on the dashboard, you must do the following:

  1. Slow down your vehicle to prevent further damage.
  2. Do not accelerate hard.
  3. In the case of towing a trailer, unload the cargo to reduce the load.
  4. Park your vehicle at a safe place.
  5. Turn off the vehicle for a minimum of 10 seconds.
  6. Restart the engine.

If the lights flash again while driving the vehicle, it’s time to contact your service mechanic immediately.

Trying with the steering wheel

You can try the following in addition to the above-mentioned method:

Without turning on the car ignition, turn the steering wheel to the extreme left and to the extreme right. Repeat it a couple of times. It releases any pressure built up in the power steering assembly.

Gas pedal

Here’s another manual way to clear the check engine light.

Gas pedal
  1. Release the gas pedal. Ensure you release it fully.
  2. Turn on the ignition and wait for 3 seconds.
  3. Now hard press the gas pedal.
  4. Release the gas pedal
  5. Repeat steps 3 and 4 for five to six times.
  6. After a few seconds, hard press the gas pedal to the extreme and let it be there for 10 seconds.
  7. You may see CEL blinking.
  8. Release the gas pedal.
  9. Wait for around 10 seconds.
  10. Again hard press the gas pedal. Keep it pressed for more than 10 seconds.
  11. Release the gas pedal again with CEL lights continuously blinking.
  12. Start the car. Most probably, the check engine lights won’t flash when the car is on.

How to prevent the CEL from turning on again?

All modern vehicles display check engine lights if they detect any malfunction in any of the car’s mechanisms. The solution to prevent CEL from turning on again is very straightforward. Taking care of your vehicle and servicing it regularly will keep the vehicle’s performance high. 

Maintaining your car regularly saves you from potential future troubles. Periodic oil changes, replacing air filters, tire rotations, checking the engine and other components, replacing worn or worn-out parts or cables with new ones, and using quality fuel, are all part of regular maintenance.

You must also avoid rash driving, which includes hard acceleration, sudden braking, overspeeding, etc.

If the check engine light appears on the screen, it is best to consult a professional mechanic immediately. Prolonging and ignoring the warning lights may result in severe damage, necessitating a significant financial outlay to repair.

Frequently Asked Questions (FAQs)

How do you reset the check engine light with a gas pedal?

Resetting the check engine light with a gas pedal involves pressing and releasing the gas pedal. The activity needs to be repeated five to six times to reset the CEL.

Do you have to manually reset the check engine light?

Several methods are available, either manual or automatic, to reset the check engine light on a vehicle. Manual methods involve removing the fuse and disconnecting the battery. Other methods require resting the vehicle for a few minutes to automatically free up the system’s memory and reset the check engine lights.

How do you reset the check engine light without disconnecting the battery?

You can reset the check engine light without disconnecting the battery by:
☑️ Gas pedal method.
☑️ Turning off the car for a while and then turning it on.
☑️ Trying with the steering wheel.
☑️ Using an OBD scanner.

How do you clear engine codes without a scanner?

You can clear engine codes without a scanner by disconnecting the battery.

Do you have to reset the check engine light after a loose gas cap?

Yes, a loose gas cap could be the reason for flashing check engine lights. Once you fix the loose gas cap, it’s essential to reset the check engine light. A few times, it may reset on its own, but it’s better to reset from our side to be safe.


A modern car is equipped with a dashboard that displays lights. These lights are error warnings, notifying you of a possible malfunction in the car’s mechanism.

Whenever you notice a warning light, you must immediately address it to get it resolved. Otherwise, it may result in serious damage to the vehicle, asking you to spend a fortune on the repairs.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top