Can You Permanently Delete Engine Codes? Here's How It Works

Your car might display a check engine light, and no matter what you do, it won't go away. Even after using an OBD scanner to diagnose and repair the issue, the light refuses to go away. This can be annoying, at the very least. It can be a reason to panic in certain cases, which is why many drivers are eager to deal with the issue as soon as possible.

Clearing the DTCs highlights

• Difficulty level:Low
• Needed scan tools:Professional tool or app
• Additional equipment:No other tools needed
• Timeneeded:10-15 minutes
• Price in a shop:$150 - $250
• DIY repair:Possible

Understanding engine codes

You may not be aware that your car, truck, or bus has an intelligent system that diagnoses different parts of the vehicle every time. When the engine, the body, or any other part of the vehicle performs differently from what is expected, it diagnoses the problem causing the issue. It communicates this to you via the dashboard. This communication is done using a warning light. As for the engine, this is done via the 'check engine light' or CEL.

The vehicle has an onboard diagnostic and reporting capability that stores codes that make a warning light pop up. The onboard diagnostic or OBD system can be accessed using a compatible diagnostic tool that uses the EOBD socket. This socket is normally found below the steering wheel but before you reach the brake pedal and the accelerator.

Once you insert the diagnostic scanner, an engine diagnostic code, also called a Diagnostic Trouble Code (DTC), is displayed on the scanner. DTCs are five-digit codes stored in the OBD and are used to identify a specific problem in the car. In the case of engine codes, the code should read something like P0606 or P0782. This combination of letters and numerals will give you a generic or a manufacturer-specific error code.

Note that an engine code does not tell which specific engine part needs replacing or repair. However, it gives you or your mechanic a good idea of what to test to properly and correctly diagnose and fix the issue.

Deleting engine codes

To eliminate the check engine light from your car's dashboard, you must first delete the error code causing it. By properly diagnosing the root cause of a problem, you have a great chance of eliminating the error code and, subsequently, the CEL. This is the proper way of deleting error codes.

As mentioned earlier, stubborn error codes don't seem to agree with the diagnostic scanners or the hands of a professional mechanic. Even after carefully exploring all possible avenues of solving a particular issue, some codes might defy you.

Can you permanently delete engine error codes?

Yes, it is possible to delete an engine error code permanently. But the question you should ask yourself is, is it safe to do that? Deleting an error code means turning the check engine light. Remember, hundreds, if not thousands, of error codes are associated with the engine. Any one of the codes will cause the check engine light to come on.

The light could be coming on because of a stubborn spark plug code, and you may decide to turn the CEL off for good. But what happens when the P0101 code is sent to the OBD? The Mass Air Flow circuit whose code has been sent will continue deteriorating because the CEL has been disabled.

Methods of deleting error codes and disabling the CEL

1) Continue driving your car

Your vehicle retunes itself regularly. The vehicle's systems diagnose and reset or retune themselves so that wrong codes are internally removed. This means that when you see the check engine light, it might help if you continue driving the vehicle for a day or two to see whether the warning light will disappear. If the error code still causes the check engine light to light up after driving for three days, it is time to consider the next option.

2) Turn the ignition ON and then OFF three times

The same self-diagnosis of the vehicle works when you turn the engine ON and OFF three times. It is like when the IT personnel tells you to switch off your computer and turn it on to see whether a certain problem goes away. The vehicle's ECU resets all the trouble codes when you turn the engine on and off the car three times. After this test, drive the vehicle and see whether the CEL will go away.

If, after switching the vehicle on and off three consecutive times, the check engine light remains, then it means there is nothing wrong with the vehicle's error codes. It also means that the vehicle's software works just fine, and it is time to consider the third option.

3) Disconnect and reconnect the battery

This trick should work for both new and older cars. It requires disconnecting the battery and leaving the vehicle for about 20 minutes. Disconnect the battery's positive power cable and ensure the cables don't touch.

Turn the ignition to the On and OFF position three consecutive times. This step clears all the emissions data and all bad records from the car's memory. Reconnect the positive cable and turn on the engine. Wait for a minute; the check engine light should be gone. If this fails to send the CEL away, it is time for the fourth option.

4) Use an OBD scanner

An OBD II scanner, which can for as low as $40, is a great investment for every DIY car enthusiast. When connected to the vehicle via the EOBD, this gadget will scan ECU and give you all the errors affecting the vehicle.

How to use an OBD scanner/ reader:

• Start by inserting the scanner into the OBD port in the vehicle. The port is located under the dash around the driver's knees. For some vehicles, you may find the port in the fuse box.
• Turn the ignition to the ON position and Press the enter button on the scanner to turn it on. Do not start the vehicle.
• The scanner will start communicating with the car's computer, and once done analyzing, you will see the error codes displayed on the scanner. Make a note of the codes. Work on the codes that can be corrected first.
• Press the 'scroll' button on the scanner and find the 'erase' button. The error code and check engine light will disappear when you press the erase button.
• Disrupt the negative cable from the battery's terminal to reset the vehicle's computer. This measure will drain all residual energy from the capacitor. Leave the battery detached for about 15 minutes and then connect it.

5) Remove the check engine light fuse

Removing the check engine light fuse has been known to delete the CEL on the dashboard. It will eliminate associated error codes and help reset the vehicle's computer. To start this procedure, you should trace the ECU, which is normally found near the glove compartment or near the engine. It's a double fuse. It is imperative that you consult the car's manual while removing the CEL fuse.

Connect the OBD II to the car. Turn the ignition to the ON position. Read the codes on the OBD and erase them. Remove the key and turn off the OBD.

You should first disconnect the battery to avoid any damage to the ECU. Once you have access to the ECU, remove the check engine fuse for about a minute. You should then connect the battery and start the car. If the CEL comes on, then the engine has a problem, and you may need to visit a mechanic soon.

Is it safe to permanently delete engine codes?

It is wrong to permanently delete engine codes before first resolving the underlying issues causing these codes. Without first resolving the issues causing the check engine light to come on, you risk destroying your vehicle and even risking your life.

Though it might sound ridiculous, several online sources describe how you can permanently delete engine codes. Here are a few easy steps to follow;

• Park the car on level ground. Engage the parking brake.
• Open the hood and disconnect the negative and positive cables from the battery. Ensure the cables don't come into contact.
• Switch the ignition key ON and OFF positions about five times. Then push the horn and hold for 30 seconds.
• Reconnect the positive battery cable followed by the negative cable.
• Start the car and let the engine warm up. The check engine light should no longer be seen.

Conclusion

As pointed out earlier, only delete the engine codes permanently if you have resolved the underlying issues. Given there are several ways to delete these codes, pick the simple ones and leave the complex ones to a professional.