How To Use a OBDII Scan Tool

Your check engine light is on, and it’s beginning to worry you quite a bit. The flashing yellow OBDII trouble code indicator is known as the Malfunction Indicator Lamp, and it’s a way to help identify what’s wrong in your vehicle. Many people complain nowadays that modern cars are nothing more than just a collection of computers. Although many people may complain, these computers help you diagnose problems with your vehicle. These computers are known as the On Board Diagnostic System or the OBDII system that comes standard in every vehicle built since 1996. The benefit of using the OBDII system is easy to do, and if you’ve got a service light on you can use a OBDII scan tool to help you fix your vehicle.

These scan tools are devices that allow you to read the alphanumeric codes in your diagnostic computer. The OBDII scan tool works as a gateway into your car in order to get to that information you need. There are many different types of OBDII scanners available on the market today. Although many earlier scanners used to be expensive and clunky, modern OBDII scan tools can now even be accessed through your mobile phone. So if you’ve got a check engine code on in your vehicle, use these steps to properly use a OBDII scan tool to check and clear your codes.

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How to use a OBDII scan tool

  1. Find OBDII Port – Before you can use your OBDII scanner, you’ll need to locate your OBDII port. Most of these ports are found underneath your dashboard, near your knees. Some of these OBDII ports can be hidden or hard to reach, so don’t waste time by fumbling about. Take the time to properly search for this port before attempting to connect to it.
  2. Connect your OBDII scan tool – Connect the communication cable from your OBDII scan tool.
  3. Power – Although there are many versions of a OBDII scan tool with internal power, most use the car’s power. So in order to turn on your OBDII scan tool, you’ll need to insert your ignition key and turn it to the “ON” position.
  4. Follow instructions – You can read the snapshot or read the error codes by cycling through the menu of your particular OBDII scan tool. Every model is different so make sure to follow instructions to get the alphanumeric code in question.
  5. Look up the trouble code – Althoguh most OBDII trouble codes mean the same thing no matter who makes the vehicle, there are some that are model specific. To get a good read on exactly what’s going on with your car, look up your OBDII trouble code using your year, make and model.

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OBDII Scan Tool Common Questions

Q : My OBDII trouble code doesn’t make sense – Although it’s not common, many times your scan tool may not have the right language or communication key to read the trouble codes stored inside your car. When this happens, you can rent or head to your local dealership to get the accurate OBDII scan tool for your vehicle.

Q: I read my OBDII code and replaced the part but the code is still there – This is a common problem and one that many people fall into unfortunately. When you see a OBDII trouble code in your vehicle for your oxygen sensor let’s say, don’t blindly replace it. The cause of the problem could be further upstream or in another area of your vehicle. Make sure you don’t jump to conclusions and blindly replace or install parts.

Q: My OBDII Scan tool doesn’t seem to work – If you’ve tried a generic scanner but it reports no stored trouble codes, chances are you need a model specific unit. Make sure to check with your dealership to see how they can help you.


Want to learn more about how to use your OBDII scan tool? Want to find the best deals on a wireless OBDII scanner or Bluetooth scan tool? Head over to our online store to discover the best prices on the best OBDII phone apps and scanners available today.

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