Red light is always on

[Humam Helfawi]

Hi,

I have NodeMCU ESP32. At some point, the board red light is always on and it prevents me from uploading a new sketch. I tried to disconnect all pins and nothing happened. The same red light still on. I unplugged the power supply and re-plug it again. The red light is still on but I could flash a sketch for once after that I could not repeat the process.

The error I got while flashing is:
A fatal error occurred: Timed out waiting for packet content

P.S. I am using Arduino IDE
Any clue is much appreciated!

[ESP_Angus]

Hi Humam,

Do you have a link to the exact development board you have? Or even better a schematic? There are a number of "NodeMCU ESP32" boards from different vendors so it's hard to diagnose otherwise.

Thanks,

Angus

[dave111]

My Wemos Lolin32 lite has also started flickering it's red charging LED a while back. I do not experience flashing issues, nor apparently any other issues related to this. But it is giving me the willies. Problem occurs on multiple Lolin32 lite boards. And it doesn't make a difference whether there is a battery attached to the charging port, or not.

The problem appears to be similar to what is described in this video: https://www.youtube.com/watch?v=cbWxf7nmuj8

But trying out several USB cables and power supplies does not change the outcome.

[Humam Helfawi]

Hi Humam,

Do you have a link to the exact development board you have? Or even better a schematic? There are a number of "NodeMCU ESP32" boards from different vendors so it's hard to diagnose otherwise.

Thanks,

Angus

Hi Angus,
Thank you very much for your reply. This the link https://www.amazon.com/dp/B0718T232Z/

[Humam Helfawi]

My Wemos Lolin32 lite has also started flickering it's red charging LED a while back. I do not experience flashing issues, nor apparently any other issues related to this. But it is giving me the willies. Problem occurs on multiple Lolin32 lite boards. And it doesn't make a difference whether there is a battery attached to the charging port, or not.

The problem appears to be similar to what is described in this video: https://www.youtube.com/watch?v=cbWxf7nmuj8

But trying out several USB cables and power supplies does not change the outcome.

Thanks for your reply. I will have a look on the video.

[ESP_Angus]

Thank you very much for your reply. This the link https://www.amazon.com/dp/B0718T232Z/

Thanks for the link. According to the "HiLetGo" schematic on this site, the red LED is the power LED so it should be always on when the board is connected to USB.

The blue LED on the schematic is connected to GPIO2. This pin should be low during flashing, so you would expect this LED to be off.

Is it possible there's another root cause? Can you flash successfully if you hold down the BOOT button while flashing? How about holding down the BOOT button and tapping (press and release) the EN button while the flash process is starting?

If none of those tips help, can you please give the full esptool.py output when the upload fails.

[Humam Helfawi]

Thanks for the link. According to the "HiLetGo" schematic on this site, the red LED is the power LED so it should be always on when the board is connected to USB.

The blue LED on the schematic is connected to GPIO2. This pin should be low during flashing, so you would expect this LED to be off.

Is it possible there's another root cause? Can you flash successfully if you hold down the BOOT button while flashing? How about holding down the BOOT button and tapping (press and release) the EN button while the flash process is starting?

If none of those tips help, can you please give the full esptool.py output when the upload fails.

Thank you very much for your reply.

About the red light, it is really wired since it was not on before (I get confused.. maybe it was there but I did not notice since it was working so I am not 100% sure)

I tried your suggestion with no luck. The full output is :

esptool.py v2.3.1
Connecting........_____....._____....._____....._____....._____....._____....._____....._____....._____.....____An error occurred while uploading the sketch
_

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header

[mikemoy]

Try sticking a 0.1uf -0.22uf from pin 3 (EN) to gnd.

[ESP_Angus]

Hi Humam,

If it doesn't work even when holding boot BOOT and tapping EN during the upload, the hardware is probably faulty in some way. The easiest option may be to get a new development board.

Angus