Mastering Car Diagnostics: How To Use OBD2 Scanner

Mastering Car Diagnostics: How To Use OBD2 Scanner
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As with all gadgets and equipment, you need to know and understand how to use your tools properly for the best results. This rule includes scan tools and the same will be true for the OBD2 scanner (also called OBD-II scanners) and all the great features included with the device to make it much easier to use.

In this article, we will take a look at how to use it so you do not need to take your car to an auto shop. Knowing how to use your OBD2 scanner may save you time and money while you learn the whims of your vehicle.

Read on and find out how to use your OBD2 scanner the right way so you can enjoy the full benefits of its features.

How to Use an OBD2 Scanner

It is not difficult to use an OBD2 scanner to check for error codes when your check engine light comes on. This scan tool is a handy addition to your emergency toolbox and needs to be in every vehicle’s collection of tools.

Follow these steps to make it much easier for you to use these scan tools and help find the problem quickly and easily.

  1. Get your OBD2 scanner’s user’s manual ready and keep it close at hand
  2. Locate the OBD2 port which can be found just below the steering column of your vehicle
  3. You can lift the steering wheel up if you need more space to access the port
  4. Connect the small side of the OBD2 scanner cable to the scanner tool
  5. Make sure your vehicle is turned off and there is no power on the port
  6. Plug the larger side of the cable into the 16-pin connector of your car
  7. If you have a self-powered scanner with its own power source you can turn it on
  8. For a scanner without its own power source, you need to provide power to it via the port
  9. Turn the ignition of your car to the on position but do not start the engine
  10. You can now turn the scanner on and wait for it to establish a connection and initialize
  11. When it is done you will see it waits for you to press the scan button so it can start scanning
  12. You need to provide the necessary information such as the VIN number, the model of your car, and the type of engine
  13. Not all OBD2 scanners are the same but they all have the start button to begin the process
  14. Depending on the model of your scanner you need to wait for it to tell you that it is done scanning
  15. Once the scan is completed you will be able to see the error codes it may have found with a description of the code
  16. From the menu of the scanner, you can now access the list of error codes by selecting it
  17. If you do not have a textual definition of the code you can easily find it in the user’s manual
  18. If you do not have the manual at hand you can easily search for the codes online and find the definitions
  19. Save or record all the information the scanner provides you with and you can turn off the car and scanner

Study the manual to see how to use all the features and functions available on your OBD2 scanner for the best results. Also, see this YouTube video for the basic operating instructions of any type of OBD2 scanner to increase your know-how.

They Are Not Difficult To Use

All OBD2 scanners come included with a manual which makes it much easier to use them and to understand the error codes. Code readers and scanners are user-friendly and provide you with the necessary instructions on how to use them.

OBD2 scanners come with a variety of features and functions included that make using these diagnostic tools easier to use. The most basic code readers provide you with code scanning and a display of error codes for your information and are quite cheap.

Other more advanced code scanners may come with diagnostic tools included and provide you with the definitions of the codes. These types of scanners are available in a wide range of price ranges from around a hundred dollars and up to a thousand dollars and more.

The OBD2 scanners that include many advanced features and functions are mostly used by professional mechanics and are quite expensive. Another very easy and quick option is to make use of the OBD2 scanner apps that can be used on your smartphone.

Why Do You Need an OBD2 Scanner

You might be wondering why you need an OBD2 scanner if most of the work needs to be done by a professional mechanic. By using an OBD2 scanner or a basic code reader, you will have a much better understanding of your vehicle.

It will also help you to understand the need to maintain all the systems on your vehicle so it provides you with the best service. Keeping all the systems in the best condition will help to prolong the life of your car and prevent unnecessary and costly breakdowns.

Using an OBD2 scanner will also help you learn what the different generic codes stand for and how to rectify the related problems.

Different Error Codes

There are different error codes picked up by these scan tools for every system in your vehicle and they all start basically with a letter and then the number. You can easily distinguish through the first letter in what system the errors occur in your vehicle for quick and easy correction.

Normally the P in the error code stands for everything that has to do with the power train system of your vehicle. This may include the ignition system, the fuel system, emissions, and other general problems that occur with the engine.

The C indicates that the error originates from the chassis systems and may include everything that has to do with that. This includes the brake system and other mechanics and mechanisms that are found in the undercarriage such as the suspension and the steering system.

An error code starting with a B will have to do with problems that occur inside the cabin of your car. This includes everything to do with the seat belt and other seat sensors, power seating errors, and also problems with the airbags.

Auto mechanic using car diagnostic scan tool

Different Types Of OBD2 Scanners

There are many different brands and models with many different functions available on the market to help find the problem. We will take a look at the different types of scanners, what they are good for, and how they can help you.

The Most Basic OBD2 Scanner

This type of scanner can be used to read the error codes provided by the electron control unit of your vehicle. They can also be used to reset the warning lights when the check engine light of your vehicle comes on.

Bluetooth OBD2 Scanner

This scanner will connect to your system via a Bluetooth adaptor so you do not need to have a cable to connect.  A Bluetooth OBD2 scanner is great for when you want to walk around your car while using the diagnostic tools of the scanner.

DIY Scanner Or Rode Reader

If you are looking for a basic diagnostic tool to keep in the emergency toolbox in your vehicle, this is the one to use. It provides you with all the basic functions you need for those easy corrections that can be done by anyone.

The Professional OBD2 Scanner

These scanners come with many advanced functions included to provide you with diagnostic tools and different types of fault codes with textual definitions. These may include such things as fuel consumption and emission control to name only a few of the many advanced features.

They also provide you with bi-directional communications so you can control most of the functions of the vehicle from the device. Some of these advanced OBD2 scanners come with functions to reprogram your car keys and even perform Electronic Control Unit coding.

Professional OBD2 scanners are mostly used by experts and professional mechanics when they run diagnostics checks on your vehicle for serious vehicle repairs. They are able to pick up any important diagnostic code that is present and relevant.

These scanners are also very expensive and difficult to use by those who have little to no knowledge of cars and their different systems. They’re best suited to people who are used to automotive tools and repairs.

Can an OBD2 Scanner Fix Your Car?

An OBD2 scanner can not fix your car and is basically used for diagnostic purposes and to read error engine codes. It will detect the error codes from the ELU and report them to you on the display of the scanner.

With the data collected and saved by the OBD2 scanner, you can now do the corrections on the car to fix the problems. This is also how experts do fault-finding on your vehicle so they can proceed with the necessary repairs.

OBD2 scanners can be used to clear the pending error codes displayed on the viewing screen and turn off the check engine light. You can also use them to turn off all warning lights but this should only be done when all repairs on the vehicle are completed.

Bluetooth Enabled OBD2 Scanner: Steps on How To Use the Device

A Bluetooth-enabled OBD2 scanner is among the most seasonable scanners due to its portability. Using it is also easy and offers highly crucial information. Because it is wireless, you do not need to connect it through cable or any extra diagnostic equipment. All you will need is the scanner and your phone.

Using the scan tool’s mobile app, you can see your vehicle’s data on the phone at any time you wish. Below, we share three easy steps to guide you as you start using a Carly Bluetooth OBD2 scanner.

  • Plug in your Carly OBD2 scan tool into the OBD port of your vehicle

The OBD-II port of your vehicle is typically located under the steering wheel or towards the gas pedal’s left. The port is a tiny plug that helps in connecting your adapter to all the ECUs in your car. You will find OBD2 diagnostic ports in most cars manufactured later than 2001. However, if you cannot locate it, you can check from the car’s instruction manual.

  • Turn the car’s engine on

After you ignite the engine, your OBD2 scanner receives data from the vehicle’s components and systems.

  • Turn the phone’s Bluetooth on and launch the OBD2 scan tool mobile app

Ensure that the mobile app you download is compatible with your OBD2 scanner. If yours is the Carly Universal Adapter, the Carly app on iOS and Android devices is good for you.

Then, click on “connect” after you launch the app. This establishes a link between your phone and the Carly Scanner via Bluetooth.

By creating the connection, you can officially begin having the control you desire over the car. Of course, a fantastic way to get started is to learn as much as possible about your car’s health and familiarize yourself with trouble codes like the check engine light. Below, we discuss the conveniences brought about by this scanner.

What You Can Do With These OBD2 Scanners

Since they have unique features, what you can do varies according to the particular OBD2 scanner you have. Below are all features you can access with a Carly Scanner.

Manufacturer Diagnostics and OBD: Error code clearing and reading

You can read and then clear basic OBD codes using the diagnostic property. This refers to every error code pertaining only to your car’s engine. For instance, you can assess engine codes like the check engine light.

In addition, you can read diagnostic trouble codes (manufacturer-specific codes). Manufacturer-specific codes are errors in every other system like airbags, the ABS, and brakes. 

Through a diagnostic check, you can identify the following:

  • Every active code on the vehicle, like the warning light
  • The extent level of error codes
  • Definition of the code to know what it stands for
  • The general state and health of the car (established by how many issues are present and how severe they are)

In addition, a feature known as Smart Mechanic enables you to access data accessible to professional mechanics. For instance, you can come across expert code descriptions, receive repair tips, and get predictive analytics on every error code. This is an excellent feature and helps better understand fault codes and how to fix them personally.

Coding: Car Customization

If you are a car fanatic, you probably also love coding. Coding lets you enable and disable default features of the car that the vehicle manufacturer predetermines. Coding the car is simple, using the intuitive user interface of Carly. You will find a list of your car’s coding options on the Carly application.

With a single tap, you can unlock new functionality in your vehicle. Nonetheless, if you wish to undo the change made, you can restore it to its default settings quickly.

Some of the common car codings are:

  1. Customize headlights and welcome
  2. Disable automatic start/stop network
  3. Lock doors automatically after attaining certain speeds
  4. Use the car key to roll the windows up and down
  5. Real-time parameters: Read out live data

Furthermore, if you wish to learn more about the current state of your car, it is possible to track live parameters. For instance, you see pressure and temperature values or check the pressure of the turbo boost. This is mainly instrumental when fault codes like the check engine light go on, and you wish to understand more concerning the engine parameters.

Checking for Used Cars: Mileage Fraud Detection

Used Car is valuable if you want to buy or sell used cars. If buying, you get to ascertain that your car of interest is not illegally manipulated. And to check whether the car has undergone illegal manipulation, Carly provides an accurate mileage report. From this, you can tell whether the actual mileage differs from that displayed on the speedometer. If the values differ, you can be sure that the odometer is doctored and steer far away from buying the car.

DIY Maintenance: Guideline on Performance of Easy Maintenance

You are charged numerous times for basic automotive repairs and maintenance that you could instead do easily on your own. Through the car maintenance feature, you get clear guidelines to adhere to as you perform basic maintenance on your own. Thus, you can stop entirely relying on mechanics and save the extra buck.

Emission Test: Make Sure To Pass the Emission Test

Before taking an official emission test, perform a test of your own using the Carly App to ascertain your probability of passing. Carly App scans every emissions control system of your car. Therefore, you get to know what needs fixing to get your car back in shape before the actual test.

Digital Garage: Get the Diagnostic Reports of Your Car

Having your car’s diagnostic check history is essential for your mechanic. In addition, it can be a valuable means of ensuring that mechanics do not cause further damage to your car after taking it to the repair shop. If a new issue emerges, you can then prove to your mechanic that the issue did not exist before taking the car to them.


Now that you understand how to use OBD2 scanner you will be able to understand the need to know the various trouble codes. When you know the diagnostic trouble code, you can keep your vehicle in top condition and safe for you and your loved ones to travel in.


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