If you are using an ESP8266 and it is not responding, don’t panic! To fix the problem, try doing the following things. In this blog post, we will walk you through some of the most common solutions. Keep in mind that these solutions may not work for everyone, so be prepared to experiment a little bit. Let’s get started!
What Is ESP8266?
The chip has a full TCP/IP stack and microcontroller capability.
ESP8266 was first introduced to the public in an issue of Serbo Croatian magazine “Monitor” in May 2014. The chip quickly gained popularity among hardware developers and hobbyists due to its low price, small size, built-in WiFi capabilities, and programming flexibility.
Since then, ESP8266 has been widely used in a large variety of applications ranging from home automation to industrial sensor networks. 
ESP8266 Not Responding: What to Do?
If your ESP8266 chip seems unresponsive, don’t fear! There are a few steps you can take to troubleshoot the problem.
- Check the power supply. The ESP8266 chip requires a specific amount of current that must be provided by the power supply. The minimum current required is 300mA. Make sure to use a high-powered USB port if you are powering the chip through the USB port. Some lower-powered USB ports cannot provide enough current for the ESP8266 and will cause the chip to reset itself frequently or not work at all.
- Check the wiring. Make sure that all of the wires connected to the ESP8266 chip are secure and correctly connected.
- Try a different power supply. If you are using a USB port to power the chip, try connecting it to a different USB port on your computer or use a different type of power supply.
- Try a different ESP8266 chip. It is possible that the ESP8266 chip you are using is defective. Try another ESP8266 chip to see if it works better.
- Check for interference. If you are using the ESP8266 in an environment with a lot of electronic noise, such as near fluorescent lights or motors, this can interfere with the signal from the chip and cause it to reset itself frequently or not work at all. Try moving the ESP8266 to a different location to see if this improves the situation.
- Check the software. Make sure that the software you are using to program the ESP8266 is compatible with the chip. Older versions of the Arduino IDE may not work correctly with the ESP8266. Try using a different IDE or programming environment. 
- Update the firmware. The ESP8266 chip comes with a built-in web server, but it can be difficult to access if the firmware is out of date. Try updating the firmware on the chip to see if this helps fix the issue.
- Try a different computer. If you are trying to program the ESP8266 from a Windows computer, try using a Mac or Linux computer instead. There have been reports of issues when trying to program the ESP8266 from a Windows computer.
- Contact the manufacturer. If you have tried all of the above and are still having issues, contact the manufacturer of the ESP8266 chip for help.
- Check your code. If you are sure that the power supply, wiring, and software are all working correctly, then the issue may be with your code. Try running a simple program on the ESP8266 to see if it works correctly. If not, then there may be an issue with your code that is causing the chip to reset itself or not work properly. Try checking for errors in your code and make sure that all of the libraries you are using are compatible with the ESP8266 chip. 
No serial data received
First, check the wiring to make sure that the TX and RX lines are correctly connected to the ESP8266 chip. If they are, then try using a different power supply or USB port. If you are still not seeing any data being received, then the issue may be with the software you are using to program the ESP8266. Try using a different IDE or programming environment.
Invalid head of packet (0xXX)
One of the most common issues that can occur when programming the ESP8266 is the “invalid head of packet” error. This error can be caused by a number of things, but is usually due to an incorrect baud rate or a bad connection. If you are getting this error, first check your baud rate and make sure it is set correctly. If it is, then check your connections to see if anything is loose or damaged. Finally, if all else fails, you can try resetting the ESP8266. To do this, simply press and hold the reset button on the device for a few seconds. This should clear any errors and allow you to continue programming the device. 
A serial exception error occurred
If you’re using Arduino IDE, go to File > Preferences > Additional Boards Manager URLs and enter the following link: http://arduino.esp8266.com/stable/package_esp8266com_index.jsonOnce you’ve added the URL, open the Boards Manager by going to Tools > Board > Boards Manager… Search for esp8266 and install the latest version. After installation is complete, restart Arduino IDE. Now open your sketch and try uploading it again. If you still can’t upload your sketch, try these tips:
- Check that you have the most recent version of the esp8266 board package installed. You can update it from within the Arduino IDE by going to Tools > Board > Boards Manager…
- Make sure you’re using the right port. The ESP8266 will show up as a serial device when it’s connected to your computer. The name of the serial port will be different on Mac, Windows, and Linux. On Mac, it will look something like /dev/tty.SLAB_USBtoUART. On Windows, it will be a COM port, like COM3 or COM4. And on Linux, it will look like /dev/ttyUSB0.
- Try resetting the ESP8266 by pressing the reset button on the board before you upload your sketch.
- If you’re still having trouble uploading your sketch, please post in the forums with as much detail as possible about your setup and the problem you’re having.
- This error can also occur if the baud rate is set incorrectly. The ESP8266 should be set to 115200 baud. To do this, go to Tools > Board and select the correct board from the list. Then go to Tools > Upload Speed and select 115200.
- If you see this error when trying to connect to the ESP8266 via serial terminal, it means that the wrong baud rate is selected. The ESP8266 should be set to 115200 baud, which is the default for most boards. To change the baud rate, go to Tools > Serial Port and select the correct port from the dropdown menu. Then go to Tools > Upload Speed and select 115200. 
Why is my ESP8266 not working?
There can be a number of reasons why your ESP8266 is not working. Here are some of the most common issues:
- The wrong firmware is installed on your ESP8266.
- Your ESP8266 is not properly powered.
- The baud rate is not set correctly.
- The AT commands are not being sent properly.
- There is a problem with the hardware.
How do I reset my ESP8266?
If your ESP8266 is not responding, you can try resetting it. To do this, simply press the reset button on your ESP8266 for a few seconds. This will reset the device and hopefully fix the issue.
How do I power my ESP8266?
You can power your ESP8266 using a USB cable connected to a computer or USB power adapter.
If you are using an external power supply, make sure that it is properly connected and provides enough power.
What is the baud rate?
The baud rate is the speed at which data is transferred between two devices. In order to communicate with your ESP8266, you will need to set the baud rate to match the speed of your ESP8266. The baud rate is typically set in the firmware of your ESP8266.
How do I set the baud rate?
You can set the baud rate using the AT+IPR command. This command takes an argument which is the baud rate you want to use. For example, to set the baud rate to 115200, you would use the following command: AT+IPR=115200.
Why is ESP8266 not connected to Wi-Fi?
There are a few reasons why your ESP8266 might not be connecting to Wi-Fi. Here are some of the most common issues:
- The SSID or password is incorrect.
- The ESP8266 is not in range of the Wi-Fi router.
- The Wi-Fi router is not configured correctly.
- There is interference from other devices on the same Wi-Fi network.
How do I know if ESP8266 is working?
You can use the AT+GMR command to check the firmware version of your ESP8266. This will tell you if the device is working and what version of the firmware it is running. You can also use this command to check the chip ID, which can be used to identify the ESP8266.
Can ESP8266 work on 5V?
The ESP8266 can work with voltages ranging from 3.3V to 6V. However, it is recommended to use a voltage regulator to power the ESP8266 with 5V. This will protect the ESP8266 from damage and ensure that it operates correctly.
Useful Video: ESP is not responding
If your ESP8266 module isn’t responding, there are a few things you can do to try to fix the issue. First, check the power supply to make sure that the module is getting enough power. If that doesn’t work, try resetting the module by bringing the reset pin low for a few seconds. Finally, if all else fails, you can try reflashing the firmware on the module. With a little troubleshooting, you should be able to get your ESP8266 module up and running again in no time!