Simple Guide: How to clear OBD2 codes without a scanner?

How to Reset a Check Engine LightThe simple way of identifying and categorizing the problems is through OBD. The term “OBD” is the abbreviation of “Onboard Diagnostic,” which refers to various vehicle issues. In 1996, the OBD system was introduced to the general public, and now it is so popular. The computer sensor connected to the car identifies the problem with the vehicle. Then it gives a signal to the “service engine light.” When the “Service Engine” light turns on, the vehicle user should turn on the OBD scanner. Then, he can find a code number that refers to the vehicle’s specific problem. This article will show you how you can clear the OBD II code without using a scanner. Removing the error code both with and without using a scanner is possible. By judging the two and choosing the best one among them, you will get a better process for fixing your car.

Quick Solution:

  • Disconnect the car battery for about 15 minutes.
  • Reconnect the battery.
  • Start the car and drive for about 10 minutes.
  • Observe if the check engine light turns off.

Can I Clear The OBD II Code Without A Scanner?

If you do not use the OBD II scanner, how can you realize that the vehicle is problematic? There are two simple ways: engine light and ABS light. When the lights turn on, you will be sure that the car is difficult. 

The question may come to your mind if you can clear the OBD II code without a scanner or not. Since the scanner is essential for checking the code, it may seem impossible to remove the code without it. So, the question is natural. 

Yes, you can clear the OBD II code without the help of a scanner. There are some processes to follow for removing the OBD II code. If you maintain these steps, you can quickly clear the OBD II trouble code from your vehicle without a scanner. 

Easy steps: How can you clear OBD2 codes without a scanner?

There are some crucial steps to clear the OBD II code. We know the scanner can identify the error code and remove the number after the problem is solved. But, there is a different process of removing the error code without a scanner. 

  • Park The Cark in The Perfect Area

If you want to remove the error code, you must park your vehicle in a perfect and safe area. It is the first step because you can not repair your car everywhere. So, the safest car parking place will help you perfectly restore the vehicle and remove the code. Then stop the car by pushing the parking brake smoothly and come out to repair it.Parking your vehicle Perfect Area

  • Opening The Car’s Hood

The technical functions of the car are under the hood and the body of the vehicle. So, you have to work at the two places to identify the issue. Firstly you can try to identify the issue by opening the hood. Working in the chamber under the hood can be familiar with solving maximum types of problems. Open Car Hood

  • Disconnecting the Batteries

If you want to repair the electrical connections of the car, you have to disconnect them first. It will help you to be safe from any risk of unwanted happening. You must remove both the positive (+) and negative (–) cables from the connections. Generally, the black wires indicate negative (-) lines. The wires of the positive (+) lines are red.  disconnecting car battery

  • Loosen The Cap of the Battery Terminal

When disconnecting the batteries, you will find the caps on them. Instead of removing the caps, you can only loosen them. Do not use the cutting wrench. Loosening the battery caps slowly with a simple wrench is enough to work with the issue. Battery Terminal Loose as a Goose

  • Cycle The Ignition

You have to cycle the ignition on and off as you remove the car’s battery. It helps recheck the system. You will also see that every driver cycles it and test it for a few seconds after starting the vehicle. Continue the task 3 to 5  times. Carry on the process without running the engine. Do you know why you should do this? It will save the key from flipping in the On position. cycle the ignition key

  • Drain Out Extra Power

Some extra power will remain in the ECU. You have to drain out it and prepare the vehicle for safe use. The draining process saves the car from extreme temperature, damaged batteries, and other significant issues. 

  • Wait A Minute before Reconnecting the Battery

Although you can reconnect the battery instantly, you may way a minute for the complete security of your vehicle. It will assist in keeping the connection safe from any harmful occurrence. 

  • Attach The Cables to The Batteries

Now you have to attach the cables very carefully to the batteries. You must be careful about the positive (+) and the negative (–) lines. Do not make any mistakes. Otherwise, the system can be faulty, and you have to repair it again. How to Connect Jumper Cables

  • Turn The Engine On

At last, turn the engine on by starting the car’s ignition. Look at the engine light now. The engine light will not turn on if the vehicle’s repair is perfectly completed. The turning on of the light shows the difficulties with the vehicle’s system. Engine On

What Can I Do If The Engine Light Is On Again?

You can get the solution by following the steps mentioned above. When the engine light turns off, the problems are solved entirely. But, have you thought, what can you understand if you get the engine light on again? The situation means that you could not drain the ECU fully. You have to repeat the tasks from first to last and clear the ECU again to eliminate the problem. Next time, I hope you can remove the ECU, and the engine light will automatically turn off. 

Problems after Restoring The Code Without Scanner

Clearing the OBD II codes without a scanner is an easy process. But, there are some problems with clearing in this way. 

When you drain the extra power from the ECU, you need to reboot the electrical system. After rebooting, you will get the system easy to use again. But, some electrical functions of the car, including the clock, radio, and drive setting, should be reset. I think the problem is not comparatively big as the previous issue. When the engine light turns on, you can easily reset the electrical functions. 

The Best Way to Remove The OBD II Code With A Scanner

Although you can clear the OBD II code without a scanner, it is not the best solution. The perfect way to clear the OBD II code efficiently is to use a scanner. There are different types of scanners to use. Mainly wire and wireless scanners are the two main types. No matter what kind of scanner you use, using the device can provide you with a better experience of clearing the error codes. 

The principal tasks of the scanner are reading, diagnosing, and erasing the error codes. If a scanner can do the three jobs perfectly, you can judge it as a suitable device. 

Now you will get the steps of removing the OBD II code of a scanner. 

  • Step-1: Buy a standard scanner from the market. Almost every OBD II scanner is suitable for use with your favorite car. Then, connect the scanner to the OBD II port. The connection with the OBD cable will connect the vehicle and the scanner. Most of the cars provide you with diagnostic connectors. You will get the connector under the left of the steering wheel. When you connect your scanner with it, the device can be ready to identify your car’s issues. 
  • Step-2: Turn on the ignition to turn off all accessories. Turning the ignition is the best process of turning the stereo, and the window defrosters off. This task is a must for starting the work related to any electric connection.
  • Step-3: Take the scanner and press the READ button. It will show the issues related to the vehicle by presenting the trouble codes. The process of getting the result of the trouble code is complete at this stage. 
  • Step-4: Now, interpret the code and check which sensor made the problem with the vehicle. Change the sensor to remove the problematic situation. You have to replace the complex sensor only. You will identify by following the scanner.
  • Step-5: When repairing or replacing the problematic sensor is complete, it is time to remove the OBD II code from the scanner. You have to push the ERASE button. The step will turn off the engine light by eliminating the scanner’s trouble code. 
  • Step-6: Repairing of your vehicle is almost complete. Now, you will turn off the ignition because its task is finished. Plug out the scanner and keep it in a specific place to prepare it for subsequent use. 
  • Step-7: The last task is to start the vehicle to warm up the engine. Every vehicle’s engine needs to get the process. It makes the engines hot for a specific time and keeps them ready for subsequent use. 

Frequently Asked Questions

Is Using Scanner Better?

Identifying the OBD II trouble code is better when you use a scanner. Because you can identify the problem instantly through the scanner, if you do not take its help, you will not be able to understand the issue without opening the engine lid. But, using the scanner, you can be sure about the problem and be ready to solve it instantly. Judging all of the matters makes it easy to say that using a scanner is better than checking the problem without using it. 

My Vehicle’s Engine Light is On Without Any Code; why?

The engine light of your vehicle can not turn on without any issue. If there is any problem with the car, the light will automatically turn on. But, if any problem occurs, the OBD II scanner will show a specific code. But, if there is no code on the scanner, you can easily understand that your scanner is problematic and should be replaced. 

Can I Get The Trouble Codes Without A Scanner?

It is not a significant matter whether you have a scanner or not. Instead, the vehicle searches for issues inside it and gets ready to show the signal on the engine light anytime. Then you have to check the error code to be sure about the specific issue. 

The trouble codes identify the specific issue, not for getting surety that the car has a problem. The engine light automatically detects the problematic situation, not the scanner. 


The clearing process of the trouble codes without a scanner is straightforward. You can only do the task by repairing the vehicle without using a scanner. Disconnecting the battery is the first task. Then, drain the ECU of power entirely. If the draining process is nicely completed, you will get the result of clearing the error code. But if the error code comes back after a couple of days, you should recheck the problem and repair it carefully. You may use a wired or wireless scanner to check the vehicle. Both of the items are good. So, the choice depends on your comfort level with using it.

Kevin Nicholas is an automotive technician who is a genius at software and hardware-related issues. He manually tested more than a hundred OBD scanners and gave his honest opinion on whether the device was worth the money or not. His in-depth OBD review articles help people choose the right product, whether it is a European, American, or Asian vehicle. He completed his Automotive Specialized Training Course at Universal Technical Institute and has more than 15 years of experience in the field.

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