How To Use An OBDII Scanner: Everything You Need To Know

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What Are OBD Scanners?

OBD stands for On-Board Diagnostics. These devices were originally designed by car manufacturers as part of their warranty programs. They allow mechanics to check up on various aspects of vehicles without having to remove parts or open doors. In addition, these tools provide information about engine performance and emissions control systems. Most modern cars have one OBD port located under the dashboard near where the steering wheel would normally go. 

The first generation of OBD scanners was called OBD I. While many people still refer to all OBD scanners as OBD I, newer models include additional features such as diagnostic trouble code reading capability. Some older model cars may only come equipped with OBD I capabilities. However, most new vehicles today offer both types of scanning technology.

Why Buy An OBD II Scanner?

This device can be used for a variety of things, including diagnosing problems with your vehicle and finding out what’s wrong with it. 

There are two main reasons why you might want to purchase an OBD II scanner:

1) To get detailed troubleshooting data from your vehicle

2) To monitor your vehicle while driving in order to avoid accidents.

Keep in mind though, you will need some basic knowledge about cars before using this tool.

How Does An OBD Scanner Work?

The OBD system works like a computerized version of a mechanic. When you start your car, the ECU sends signals through wires attached to sensors inside the engine compartment. Each sensor monitors different conditions within the engine.

For example, the oxygen sensor measures the air/fuel ratio, which helps determine whether the mixture needs adjusting. Other sensors measure coolant temperature, oil pressure, battery voltage, etc. All of these readings are sent back to the ECU via the same wiring harnesses. The ECU processes the data and displays it on its display panel.

If something goes wrong with the engine, the ECU generates a signal known as a fault code. A technician uses this code to identify the specific malfunctioning component. For instance, if the fuel pump fails, the ECU will generate a P038 error code. That means the fuel pump has failed.

When you connect your OBD scanner to your vehicle, it reads the codes stored in memory. Then, it shows you exactly what went wrong.

How To Use An OBDII Scanner - Step By Step

What Can An OBD Scanner Tell You About Your Vehicle?

An OBD scanner allows you to view several kinds of information related to your vehicle. Here are just a few examples:

Fault Codes – Displays the current status of each electrical circuit in your vehicle. There are hundreds of possible faults. Many of these relate directly to mechanical components. Others indicate potential problems with electronic circuits.

Engine Data – Shows details about the condition of your engines, such as RPM levels, timing settings, and other parameters.

Coolant Temperature – Indicates the level of antifreeze in your cooling system. Too much could cause overheating and damage to internal engine components.

Oil Pressure – Tells you how well your automatic transmission is working. Low oil pressure indicates a leak somewhere in the gearbox. High pressures mean everything is fine.

Battery Voltage – Reports the charge state of your batteries. If they’re low, that’s usually because there’s not enough power being generated by the alternator. This problem should be corrected before it causes any serious issues.

Ignition Timers – Provides insight into when your ignition switches turn off and on. It also tells you when your key fob turns itself on and off.

Airbag Status – Lets you know if your airbags are armed or disarmed. Armed airbags protect passengers during collisions. They may deploy automatically at certain speeds or under certain circumstances. Disarmed ones won’t do anything unless someone presses their button.

Brake Light On / Off – Determines whether your brake lights are turned on or off. An illuminated light means your brakes have been applied. A flashing light means your brakes aren’t functioning properly.

Transmission Shift Lights – Identifies whether your manual transmissions shift up or down. When shifting gears manually, the indicator lights change color depending on where you are in the process. Green for neutral; yellow for first gear; red for second gear; blue for third gear; white for fourth gear; black for fifth gear; and gray for a sixth gear.

• Fuel Level Sensor – Measures the amount of gasoline remaining in your tank. You’ll see a green bar indicating fullness. Red bars show less than half-full tanks. Yellow bars represent empty gas containers.

Best OBD2 Scanners

How Do I Connect an OBD2 Scanner To My Car?

You need two things to get started using an OBD II scan tool:

1) Your Scanner. The best way to find out which one works best for you is to check our buyer’s guide on the best OBD2 scanners for the money.

2) A cable. Most OBD2 tools come equipped with cables that plug right in to the diagnostic port located near the steering wheel column. These cables allow you to read data from your vehicle’s computer without having to remove parts like the dashboard or dash panel. 

The latest generation of OBD2 scanners now includes built-in Wi-Fi or Bluetooth connectivity so you can easily upload all those cool scans straight to your smartphone! Just download the free app, then follow the simple instructions provided on the screen to start scanning.

Step-By-Step Guide

So, how do I scan for OBD codes? There are three basic types of OBD code readings available through most OBD2 scanners:

OBD Code Readings: This mode allows you to view information about what was happening while driving. For example, this could include engine RPM, fuel level, speedometer reading, etc.

OBD Trouble Codes: These are error messages stored within the ECU. Some trouble codes will cause problems such as misfires, stalling, overheating, etc. Others simply indicate that something isn’t working correctly.

OBD Diagnostic Data Logs: These logs contain detailed information about how well each component inside your vehicle is performing. In addition to showing you exactly what’s going wrong, these logs provide valuable insights into why your vehicle might be acting strangely.

1) You just locate your OBD2 port and plug the unit into this port directly. After doing so, you simply turn the ignition key to start the engine. A small LCD screen will light up showing various readings as well as for instructions on how to proceed. 

2) The first thing you see is usually the main page. Here you’ll find important info like your current mileage, odometer reading, battery voltage, oil pressure, temperature, airbag status, and much more. If there’s anything unusual here, it may mean that something has gone awry. It also shows if any warning lights are activated.

3) Next, scroll down to the bottom of the screen and click on “Data Logging Options.” This opens another window that lets you choose between different modes of operation. There’s no real difference among them other than their names. However, some people prefer to have everything displayed at once rather than scrolling back and forth across multiple pages. 

4) Once you’re ready to begin, just press the button labeled “Start Reading,” and wait until the display clears before clicking again. That should bring up the next page. Scrolling forward reveals additional details about whatever happened during the last time you scanned. 

5) If more than one code appears after connecting to your vehicle, don’t panic! This just indicates that your vehicle has several different problem areas. It doesn’t mean there’s anything seriously wrong with it. To help narrow down the issue, try running multiple tests at once by selecting them individually under the “Test Mode” section.

Once you’ve found the specific area causing issues, scroll back up to the top and click “Clear All Test Results” to clear everything else. If only one code shows up when connected to your vehicle, make sure you’re looking at the correct screen before clicking any buttons. 

6) The data and codes displayed may vary depending on the model year and manufacturer of your vehicle. However, they should always appear somewhere along the bottom left side of the display window. Use these codes along with other symptoms to determine whether your car needs service.

7) Some OBD2 scanners can use these codes to highlight potential problems. Clicking on the individual codes displays additional details including the severity of the fault, its location, and even some helpful tips on fixing it yourself. With cheaper models, you’ll have to rely on your car’s manual for diagnosis.

If you don’t understand anything that happens on the screen, then you should probably not try to diagnose any problem yourself. Instead, take it to someone who knows more than you do. This is especially true if there are safety issues involved. It’s also important to know how to read the codes so you can find them when they’re displayed. The following guide will help you learn more about this handy piece of equipment.