ELM327 Bluetooth Pin/Key Code – Information & Instructions

Elm327 Bluetooth Pin Code Reader

Have you ever tried to switch on your car’s engine, only to find that mysterious ‘check engine’ light as the result?

Your first instinct would be trying to connect the ECU (Engine Control Unit), only to have it fail – and the manual tells you to take the car for servicing. No, not the most reassuring statement you have ever seen.

This raises the question of how you can begin reading fault codes from your engine, without the cost of taking it for servicing and having someone else do it for you. That is where the ELM327 bluetooth pin code comes in, so read on to find out more information about it.

A Few Things to Note

Bluetooth Elm327 Obd2-Scanner

When you are in the process of looking for a great adapter for your car system, the information may confuse you. However, with sufficient knowledge of how your car system works, you will be able to avoid costly mistakes.

The car needs to register and inform you of any issues it has within the system, and it does so through the OBD or Onboard Diagnostics. These issues may include heavy emissions, low fuel, and low economy.

First introduced in 1987 as the OBD-I, this was meant to standardize the diagnostics in cars. The OBD-II came after 1996.

The OBD-II uses a complex system to connect a wide range of systems in your engine and operates at an average of 500 kbps. It can access a wide range of information because of this, such as the oil temperature, vehicle speed, and engine rpm, as well as many others.

If any of these have issues, then it sends you a warning through the ‘check engine’ light. A professional mechanic will use a handheld scanner to see where the problem is, but this is something you can do as well.

What Is the ELM327 Bluetooth Code About?

Obd Connector

This is a method of providing an easier way for you to scan the OBD-II system (Onboard Diagnostics II), to monitor any problems easily and read PIDs, as well as other codes. You do not need to pay expensive costs when you take your car for servicing, as this method proves useful for this purpose as well as if you are an expert who does not have your dedicated scanning tools at the moment.

Even though this is useful in solving your issues, there are still some things you should know about the system before you purchase it.

If you want to look deeper into this scanner, you can check it out on Amazon here: ELM327 WIFI Wireless

Any Issues to Note?

They are not many, but it is important to note that some of the cheap ones are likely to have unauthorized ELM327 microcontroller clones. These can often have unexplainable behaviors at times and cause the entire system to fail to work with certain devices.

The devices that are most affected by this are iOS devices, so if you have one it is important to select the right device for the job.

What About Compatible Hardware?

Any scanning tool that features Bluetooth chips and an ELM327 controller will have a wide variety of devices it can pair with comfortably. However, there are limits, just as with anything else.

The devices you can use include laptops, smartphones, and tablets. The phone is the best way to use the connectivity advantage – however, it might not work well with Apple products, such as iPad, iPhone, and iPod Touch, because of how Apple handles bluetooth in general.

If you are an Apple user, it is a better idea for you to use Wi-Fi ELM327 scanners and USB connections.

In addition, if you have a single unit that can act as a reader and adapter, that is an even better option.

Can You Tell if Your car Is Compatible With the system?

If your car was manufactured any time after 1996, then the answer to the question is likely yes. If you are not sure of where the port itself is located, then you can check through Google, using the model of the car, its make, and year of manufacture.

How to Pair the Device to the System

It is generally easy to pair your device to the ELM327 system unless of course, you have an Apple device. In terms of the basic rundown on the general steps, you can:

  • Plug the Bluetooth device into the OBD-II port
  • Allow the device to scan for possible connections (as you would for a normal bluetooth connection)
  • Choose the scan tool (ELM327)
  • Input the pair code

For many cases, when you buy the bluetooth scanner, you will receive some documentation that contains the pairing code, as well as any other unique directions that are different from the norm. However, if you do not have access to the documentation, there are some common codes that are useful, which are:

Pin Codes:

  1. 0000
  2. 9999
  3. 1234
  4. 6789

If they fail to work, then try other sequences of four numbers (consecutive order).

What if It Does Not Work Completely?

If you have tried all of these things and the device fails to pair with the system, then this may be due to several reasons. In the case of this occuring, try the following solutions:

  • Try alternative pairing codes
  • Attempt to pair the scanner with a different device and see if it works. This is because certain poor quality microcontrollers have issues with connecting to some devices.

One of the reasons the failure may happen is due to the limited time frame. Bluetooth can discover devices, yet when you try it again, you notice that the device is not discoverable. Consider doing the pairing within a minute of plugging the scanner into the OBD-II port, and there will likely not be an issue with connectivity.

If you have an Android device, then you can use the system in connection with apps on the Google Play store, such as Torque Pro. The advantage of these apps is that they allow you to monitor changes to the engine in real time, even when the car is running, and you can also easily read pending or logged fault codes.

Final Thoughts

While the process of interpreting and reading the codes is great in diagnosing engine issues, you must be careful with the issues you choose not to take note of –  don’t compromise on safety by ignoring the serious issues.

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Written by:

Magnus is the owner and main author of MechanicBase. He has been working as a mechanic for over 10 years, and the majority of them specialized in advanced diagnostics and troubleshooting. Certified Automotive Diagnostic Technician.