Arduino not Detected? This Solution will Help!

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In this post we are going to solve Arduino software and driver related issues which are driving some beginners crazy and we will also address some of the problems related to Arduino hardware.

We will see:

  • Why your Arduino is not detected by your computer?
  • Solutions for not detection of Arduino boards.
  • Driver Download Link.
  • How to install the driver.
  • Troubleshooting Arduino board and IDE.

You landed on this page because you could not upload your sketch to Arduino or it is not even detected by your trusty computer. Here we will discuss the possible problems why your Arduino board is not detected or why you couldn’t upload the sketch/code and we will see the recommended solutions.

Let’s starts with a common issue.

Why your Arduino is not detected by your computer?

This is a very common issue faced by most Arduino beginners and sometimes even who has intermediate experience with Arduino. Your IDE will not show the connected Arduino board and you device manager will say “unknown USB device”, when you try to fix with windows tools you will still end up not fixing the issue.

Arduino unknown USB device
Arduino unknown USB device

To find out why the Arduino boards are not detected, let’s inspect the Arduino board’s USB to serial converter chip.

A USB to serial converter module is utilized on all Arduino boards to uploading sketches to the microcontroller and also for serial communication between the computer and the main microcontroller.  

Here is an Arduino UNO clone with ATmega16U2 controller which is used as USB to serial converter, the same converter is also utilized on genuine Arduino boards.

Arduino with Atmega16U2
Arduino with Atmega16U2

The clones which utilize ATmega16U2 as USB to serial converter for the microcontroller won’t have any issues with detection.

Now let’s inspect another Arduino board clone, which doesn’t utilize ATmega16U2 for USB to serial conversion.

Arduino with CH340G chip
Arduino with CH340G chip

The above Arduino board is SMD type; this board has exactly same specification as genuine Arduino UNO. As you can see there is a difference in the USB to serial converter chip. This is called CH340G USB to serial converter chip.

You can see this on cheap Chinese Arduino clones; this chip will not be detected neither by your computer nor the IDE. You have to install CH340G driver to your computer only then your computer will recognize the device and able to upload sketches.

You can also find this CH340G chip even on Arduino nano clones as illustrated below:

Arduino Nano with CH340G chip
Arduino Nano with CH340G chip
  • Download CH340G Driver:

You can download the CH340G driver for these kinds of Arduino boards: Click Here

How to install CH340G Driver to windows Computer:

  • Download the CH340G drive from the given link.
  • Now double left-click on this icon:

  • It will ask for administrator permissions, click YES.
  • Now it will prompt you with 3 options: Install, uninstall and help.
  • Click on Install.
CH340G driver Installation
CH340G driver Installation
  • Click Install, once the driver installed it says “Driver Install Success”.
Arduino CH340G Driver Installation
Arduino CH340G Driver Installation
  • Restart your computer after installation (Important).

NOTE: Some users notified that Arduino clones which use CH340G chip are not working properly on USB 3.0. Please comment if you face similar issue.

By now majority of the problems would have been solved with Arduino boards. Now let’s discuss some other issues faced by arduino enthusiasts.

Program/sketch not uploading solutions:

These are the possible explanations why you are not able to upload sketches to Arduino and their solutions.

  • Incorrect COM port selected:

Most beginners make this mistake, they select wrong COM port. Each computer has different COM port numbers and you have to select the right one for your PC. If your Arduino board sport ATmega16U2 chip it will show you to which COM port number your board is connected to and select that one.

If your Arduino board sport a CH340G chip, it won’t show you the connect COM port number and you have try each of them that is displayed.

  • Selected wrong board at tools menu:

You have to select the correct board name. If you choose Arduino Nano for Arduino Uno, you code will not get uploaded.

  • Selected wrong processor:

You should select the right microcontroller IC number at tools menu, otherwise the code will not get uploaded.

  • Tx and Rx pins are connected to your circuit:

Whenever you are uploading a code to your Arduino board, make sure that Tx and Rx pins are not connected anywhere else in the circuit. Once you finish uploading the code, you may reconnect the Tx and Rx pins to your circuit. The Tx and Rx (pin number 0 and 1) are the pins where the code gets uploaded to the microcontroller.

  • Defective USB cable:

A defective USB cable can make your Arduino board undetectable on your computer, not even detectable on your device manager and also may cause frequent disconnection from your PC. If you find yourself in this circumstance, please replace the USB cable that connects to your computer and Arduino board.

  • Defective USB port:

A dusty / rusted USB port on your computer may cause frequent disconnections or may prevent uploading of the code altogether, this could be because the rusted USB lines may not establish proper physical contact with the USB cable.

Always connect your Arduino board to a good USB port of your computer and make sure that USB port on the Arduino board also has no physical defects. If problems arise from a particular USB port, don’t use that again.

  • Inspect for physical damages on Arduino board:

Grab a magnifying glass and take a closer look at the traces and solder joints in the board, especially on USB to serial converter chip and microcontroller IC, if you find any, try to bridge them by soldering it. If you find any physical damage on any of the components, such as cracks or burn marks, you may need to replace the component or replace the whole board.

There could be problems with microcontroller IC or with other components which are not visually inspect-able / visible or replaceable, in such case replacing the whole board is the only solution.

  • Try Reinstall the Arduino IDE:

Download a fresh copy of IDE from the official website of Arduino and install it to your computer. Re-installing the latest / same version of Arduino IDE may solve some installation issues with your computer.

There could be situations where the newer IDE didn’t work well with your Arduino board, if so please try roll backing to the previous version which you have been using before.

  • Try to upload a sketch from another computer:

This is the final troubleshooting step if you can’t get your Arduino board to work. Connect your board to another computer (with proper drivers) which is known for uploading Arduino sketches without any issues. If the issue still persist, your board has some problem and please replace your board.

By now you should be able to find issues with your Arduino and able to fix it.

If you have any further questions, please comment below, you will get a guaranteed reply from us.

My nick name is blogthor, I am a professional electronics engineer specialized in Embedded System. I am a experienced programmer and electronics hardware developer. I am the founder of this website, I am also a hobbyist, DIYer and a constant learner. I love to solve your technical queries via comment section.