Blog Car Care Advice How To Use An OBD2 Scanner (Step-By-Step Guide + 3 FAQs)
Car Care Advice

How To Use An OBD2 Scanner (Step-By-Step Guide + 3 FAQs)

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An OBD2 scanner can help you or your mechanic understand if your car’s in good shape. 

An OBD2 scanner is a diagnostic tool that connects to your car via the Diagnostic Link Connector. This is done through a wired connection, Bluetooth, or WiFi, allowing you to scan every diagnostic trouble code generated by your car’s computer.

But the question is, how to use OBD2 scanner?
In this article, we’ll show you step-by-step how to use an OBD2 scanner. We’ll also answer some related FAQs to give you a better understanding of this tool.

This Article Contains:

Let’s get started.

How To Use An OBD2 Scanner? (Step-By-Step)

Using an OBD2 car diagnostic scanner is simple and straightforward. 
Here’s a simple step-by-step guide:

Step 1: Locate The Diagnostic Link Connector

If your car was manufactured after 1996, it features a Diagnostic Link Connector (DLC) or OBD2 port.

This is a 16-pin connector located on the left side of the driver’s dashboard underneath the steering column, usually covered with a door or flap. 

In case you can’t find the OBD2 port, you can always check your owner’s manual.

Step 2: Connect Your OBD2 Code Reader Or Scanner To The DLC

After locating the DLC, make sure your car is turned off

Plug the end of the OBD2 scan tool into the Diagnostic Link Connector with an OBD2 connector cable. If you own a Bluetooth OBD2 scanner, directly insert the scanner into the OBD II port.

Next, check the scanner instructions on whether you should keep the car in ON or idle mode after connecting to the DLC. This step is important because following the wrong method can damage the scan tool app.

Following the correct instruction allows your scanner to communicate with the car’s computer. Confirm the connection to your OBD2 system by checking for a message on your OBD II scanner.

Step 3: Enter The Information Requested On The Scanner Screen

Your car has a Vehicle Identification Number (VIN). Depending on your scanner, you’ll have to enter the VIN before it can generate any OBD2 code. 

The code scanner may also request other details like your engine and model type.

Where can you find the VIN?

If the scanner requests it, you can find the VIN on a sticker normally in the lower corner of the windshield on the driver’s side. Other places include under the hood next to the latch and at the front end of the vehicle frame.

Step 4: Access The Scanner Menu For OBD Codes

Now go to the code scanner menu screen, where you can pick between the different car systems. 

Select a system so the scanner can show every active and pending code.

What’s the difference?
An active code triggers the check engine light, while a pending code indicates the failure of an emission control system.

Remember, a reoccurring pending code can become an active code if the same issue keeps popping up.

Note: The car code reader or scanner display varies depending on your scanner type. Some will reveal only a problematic diagnostic trouble code, while others let you choose which OBD2 code you want to see.

Step 5: Identify And Understand The OBD Codes

With the OBD codes displayed, it’s time for you to interpret them.

Every trouble code begins with a letter followed by a set of four digits. 
The letter in the diagnostic trouble code can be:

Now let’s understand what the set of numbers imply in a fault code:

Note down the OBD codes displayed by the scanner and turn off your car. Then carefully unplug the OBD II scan tool.

If your scanner supports it, you can also transfer the OBD codes to your laptop via a USB cable or Bluetooth.

And if you can’t seem to read live data from your OBD scanner, contact your mechanic for help. 

Step 6: Move On To Trouble Code Diagnosis

The OBD scanner or code reader tells you what’s wrong with your car, but it can’t tell you how to fix the problem.

So figure out if the error code implies a minor issue or not. 

And then, you can decide between a DIY approach or professional help. However, it’s best to take your vehicle to a certified mechanic’s shop to avoid expensive mistakes.

Step 7: Reset The Check Engine Light

Once your car’s issues are fixed, the check engine light should turn off after driving it for a little bit. But you can always use your OBD II scan tool to erase a code immediately.

Go to the main menu of your OBD2 reader and find the check engine light option. Then press the reset button.

Give it a few seconds or minutes, and the engine light should turn off.

Note: You can use the scan tool to erase an error code and stop the check engine light from lighting up temporarily if the issue isn’t fixed. However, the check engine light will illuminate again since the problem still exists.

Now that you know how to use an OBD 2 scanner, let’s answer some FAQs.

3 FAQs On How To Use OBD2 Scanner

Here are some common OBD II scanner related questions and their answers.

1. What’s The Difference Between An OBD1 And OBD2 Scanner?

OBD2 device or scan tool is a more advanced piece of technology when compared to the OBD1 scanner. 
The main differences include:

2. What Are The Different OBD II Scanner Types?

There are multiple OBD2 diagnostic code reader types available. However, they’re mainly categorized into two kinds:

1. Code Reader

An OBD2 code reader is affordable and readily available. It lets you read every fault code and clear them. 

However, the OBD2 code reader isn’t the most advanced diagnostic tool, so it can’t fully support manufacturer-specific OBD codes.

2. Scan Tool

A scan tool is an advanced car diagnostic tool that’s usually more expensive than a code reader. It also has a lot more features than a diagnostic code reader. For example, a scan tool provides access to recorded data that you can playback live.

It even reads the vehicle manufacturer and enhanced diagnostics codes, unlike a code reader. Some car scanner tools may even have diagnostic equipment like multimeters or scopes.

3. What Things Should You Consider While Buying An OBD2 Scanner?

When buying a car diagnostic tool like an OBD2 scanner, here’s what you need to consider:

Final Thoughts

The OBD 2 scanner is for everyone, whether it’s a Bluetooth scanner, a built-in one, or a handheld scanner that needs a wired connection to the OBD port. Anyone can easily detect needed vehicle repairs inexpensively with it.

The only tricky part is fixing the issue detected by your car code reader. For that, you have AutoNation Mobile Service.

They’re a mobile auto repair and maintenance solution that can fix your car issues right where you are. AutoNation Mobile Service’s professionals can even read OBD codes for you if you don’t have a scanner. 

You can reach out to them 7-days a week and enjoy an easy online booking process. 
Contact them about your OBD scanner detected troubles, and their expert mechanics will clear the codes in no time!