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Step-by-Step Guide on How To Reset Check Engine Light On GMC Sierra

A failure in the vehicle’s emissions, ignition, gasoline, or exhaust systems causes a check engine light to switch on. You’ve just started driving around in your GMC Sierra when, suddenly, the car flashes a coded warning that an internal issue might need to be reset. But not everyone knows How to Reset the Check Engine Light On a GMC Sierra.

Generally speaking, we reset by driving continuously, switching the ignition on and off, unplugging the battery, monitoring the gas tank cap, attempting to spin the steering wheel, and fixing the mass airflow sensor, O2 sensor, converter, vacuum leakage, or plug. Or if you can’t, take it to the auto shop to be serviced.

We want to highlight the possible signs that trigger resetting the check engine light. Hopefully, you won’t leave the site without having your solution.

Why Check Engine Light Comes On?

The check engine light is an advanced technology in today’s vehicles, which detects issues and signals them when the ignition system isn’t working efficiently. You can also say the on-board monitoring system’s strategy is to notify you if anything is wrong internally.

The system maintains a “trouble code” that indicates the trouble that needs to be fixed when the light turns on. In United States law, check engine lights are required to help the driver be safe by alarming them by flashing lights of potential issues.

Check Engine Light on GMC Sierra 1500 Codes

gmc sierra check engine light codes

It’s usually not wise to drive with the check engine light flashing. Remember, this technology will flash some codes that must be valued. When the blinking light appears frequently, the engine is misfiring severely, enabling unburned gasoline to escape into the exhaust system, which is the most common cause. However, look at the typical problems and codes that the Check Engine Light (CEL) indicates on the GMC Sierra.

  • Circuit board problems
  • Difficulty with emission controls
  • Problems in the ignition system
  • Misfire in the engine
  • Long used battery
  • Transmission difficulties
  • Defective or loose gas cap
  • Pressure sensor for the fuel tank
  • Corroded fuel injectors
  • RPMs quickly rise
  • Rusty spark plugs
  • Malfunctioning catalytic converter
  • The airflow sensor is dirty
  • Broken thermostat
  • An O2 sensor fault.

How to Reset Check Engine Light On GMC Sierra – Steps to Follow

gmc sierra check engine light reset

At a particular moment, we riders noticed the check engine light on the GMC Sierra flashing. But we lack the knowledge of resetting. So, how do you fix the check engine light? What could be the simple trick to turn off the check engine light? Everything will be resolved below!

4 Common Signs That Ensure GMC Sierra Reset

The check engine light often illuminates, notifying us by showing certain codes. However, the following are the primary triggers for your car:

  1. Difficulty starting the car.
  2. Another indicator to reset is harsh idling.
  3. Smoke emerging from the vehicle’s tailpipe signals that the system requires a reset.
  4. Also, fuel sensor trouble ensures resetting.

Reset Check Engine Light on GMC Sierra – Manual 6 Steps

An immediate repair or reset is necessary for an illuminated engine light since it might trigger major issues inside your car. You have some easy ways to reset your GMC Sierra engine light manually. If you are in a hurry, try these simple steps:

  1. First, turn the ignition switch off.
  2. Wear gloves and protective goggles.
  3. Find the negative terminal with a black cap and the minus sign (-). Unlike the positive terminal, marked with a red hat and a plus sign (+).
  4. Remove the negative connector from the Sierras battery, then use a wrench to loosen the nut. 
  5. Take around 30 to 60 seconds and keep it aside.
  6. After that, use your wrench to tighten the negative cable connection firmly by reconnecting it.

Start Your Engine

Do you know? The vacuum opens and stops the exhaust gas recirculation (EGR) valve on the GMC Sierra. However, start your car’s engine. The problematic valve not performing properly aims to point out the check engine light.

Continue Driving

You don’t have to stop the vehicle when the check engine light comes on while driving the Sierra. Drive through the light as it comes on because it can be a minor problem that doesn’t require immediate attention.

Turn the Ignition On and Off

You might need to turn the car on briefly before turning it off when the engine light is blinking. It’s a restart technique that can clear the error codes and turn off the light. You need to restart two or three times occasionally.

Attempt Steering Wheel

You must turn off the ignition before ensuring you’re using the steering wheel to drive. You will require left and right turns on the steering wheel. Ensure the pressure in the power steering system is released.

Disconnect Battery

Your car’s performance may decline when the battery is old and worn out. As a result, unplug the battery and then reconnect it. Keep that in mind; keep it disconnected for around 15 minutes. You will require a little elbow grease under those circumstances.

After that, start the car by inserting the key. Eventually, the data would be cleared, and the light switched off. Lastly, reconnect the battery once more, then start the ignition.

Monitoring the Gas Tank Lid

Monitoring the gas tank lid to see if you need to reset it is another crucial part. The gas cap on your GMC Sierra may be loose, damaged, lost, emitting fumes, or that gasoline is leaking. Therefore, secure the gas cap.

The component of your engine that ignites the air or fuel mixture in the combustion chamber is often the spark plug. However, damaged plugs will also affect your GMC Sierra’s performance level and engine efficiency.

Remove the Plug

A possible factor concerning aftermarket parts indicates that the car could also struggle. Meanwhile, OEM parts will benefit you.

Also, damaged ignition coils and O2 sensors, or a clogged catalytic converter might result from damaged spark plugs or plug cables, which will eventually cost more. Therefore, swap out the old ones with new ones.

Visit Service Center

Visit Service Center

If you find anything difficult, take your car to the auto shop or service center to diagnose the problem with your GMC Sierra. Sometimes, we use an OBD-II code scanner to detect the issue. Resetting is not a hard and fast job so if you follow our instructions, hopefully, you won’t have to spend the extra penny to resolve the issue.

Also Read: Fixing P0300 Code Chevy Silverado Issues

Frequently Asked Questions

How do I reset my check engine light manually?

Manually turning off or resetting the check engine light is relatively simple and can be done by performing the following actions:
1. Your key must be in the ignition.
2. Using the scanner, you can detect the issue easily.
3. Then, without removing the battery, turn the ignition on and off for one or two seconds for a hard reset.
4. Do the process 3 to 4 times.

How to reset check engine light without disconnecting battery?

Simply switch the ignition on and off for a few seconds 3 times to reset the engine management light without a battery.

How many miles does it take to reset a check engine light?

In order to get the codes, you should let the light reappear. If the check engine light reappears, drive your car for 30 to 100 miles to ensure it won’t. It does this by allowing the car’s “drive cycle” to restart, which is required for the monitoring systems to have enough time to adjust properly.

How long does it take for a check engine light to clear?

We typically turn off the negative battery cable for around 15 minutes to reset the check engine light. However, after fixing all potential problems, the engine light should never reappear.

Why is my engine light on but nothing seems wrong?

If nothing appears to be wrong with the car but the engine light flashes, you are safe to drive or you should meet with a mechanic to determine if there is a problem with the vehicle. After refilling, if the gas cap is a bit loose, the light could probably turn on. So, keep it secured.

Final Words

So, whenever you notice the check engine light on your GMC Sierra flashing, make sure you identify what’s wrong with the vehicle. We discovered why the light comes on and what codes you will get if the car has troubles. 

Plus, if you expect to reset on your own, check the manual idea as well as the other steps like engine starting, ignition turning on plus off, trying the steering wheel, disconnecting the battery, changing parts, monitoring the gas tank lid or extreme level of difficulty should be resolved by the auto shop. 

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