K2400, light blocking pads

Good morning, do the light blocking pads have any electric function? Is it really necessary to solder both sides?

Hello, and thanks.
But now … it doesnt work. When I power it up, only a red LED on the ESP-32-board glows. Nothing else.
I’m very sure that I have done all things correctly, and also the soldering joints look good.
I checked that the 5V voltage can be measured at the watchface, between VCC and GND.

What else can I do or check?

Hi @Retro,

Could you post some pictures of your K2400 so we can assist you further?
Kind regards,


Good morning, yes, here they are.

When you power up the board
Do you find a WiFi hotspot named “My K2400”?

No, definitively not.
Can I do/try something with the two buttons?

When I press and hold Button J2 and then power up, the upper LED (at 12) lights white.

Seems like the board is unfortunately not programmed.
Are you familiar with Arduino and ESP32 environment?

Only very little. But I would try it, if you send me the code and a little instruction.
Should we continue the conversation via e-mail?

Hallo VEL337,

you wrote me that I should message you personally via the forum.
But I dont find such a function. Where is it?

Go in to their profile and click on Message in the upper right corner


One way to do that:
Click on the avatar
(The pink circle of VEL337 on a reply of VEL337 image )
and then click on the blue message button.


You just reply on that message :slight_smile:


you may think that I am stupid… But when I click on the Avatar I get this

But where is the blue message-button?

Or should I really reply to the “noreplay… e-mail-adress”?

I am confused a bit…

Hi please try again.
I changed your user level from new user to basic user maybe that will fix the problem

Hallo VEL337 or somebody else,
the problem is still not solved and you dont answer my mail.
Would you please send me a new and programmed board or tell me how to program it?