The LEDs 2 and 4 doesn't light !? [solved]


On Step 11 when i test the digital control board the leds 2 and 4 never lights ??
Is it normal ?

Everything else is OK as describe on the site !

Thanks for your help

Have you inserted the MCU and is it correctly oriented?


Thanks for your answer !

Yes i’ve inserted the MCU and it’s corrctly oriented !

What is the voltage at the +5V pin on the digital board? And at the power pins of the MCU?

Other question: if you remove the MCU and try powering the board, do you have any LED lit?

Do any other LED shine? If so you swapped the 595 and 165…

The led 4 is lightning now, because of a very bad soldering

The voltage at the +5V pin on the digital board is 4.99V

When i remove the MCU, no light on any LED !

I don’t know where is the power pins of the MCU !


Does it stop shining when you push the button no4 beneath? If so, then try resoldering all the GND Pads (the ones near the pushbuttons) they are a bit hard to solder cause they are all connected to GND and thus suck up much heat (as i ca tell from my beloved 8W Soldering “Iron”)

It works
Thanks a lot, i’ve resolded the GND pads :slight_smile:

Great, thanks again