Pi Zero WH - Won't boot up

Hi Team,

I am using Pi Zero in a D.I.Y project. The pi task is to read data from a couple of PiicoDev sensors to decide on when to open/close my irrigation system’s values.

12V solenoid valves are controlled by 5V Relay Modules (2 * SKU: CE05279).
I am using an official Pi power supply. The SD card is fine as it works on the new boards. I have also tested other brands/ OS to ensure the SD card is not the root cause.

The load on the Pi would be a bit high; however, the housing box is equipped with a powerful fan controlled by a speed controller module.


  1. What would have caused the issue. I have experienced the same problem twice in the past 12 months.
  2. Is there any way to fix the faulty Pi boards.



From what I can see, this is no common issue. So it’s quite likely something unique to your setup given it has happened before. Maybe the external hardware plays a factor; back EMF from the solenoids? Hard to say.

If the same card works in another RPi then that does suggest the fault is with the RPi Zero (though it doesn’t help with what contributed to that outcome).

Not really; new boards are priced well below the parts+labor cost of repair. So there isn’t a strong repair culture out there for Raspberry Pi.


Hi Farhad
On the two 5V Relay Modules what voltage are you applying to VCC and where are you picking it up from?

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I am using an adjustable switching power supply module (20W Adjustable DC-DC Buck Converter with Digital Display; DFR0379) to feed the relays.
A laptop adapter provides 16VDC to power the module.

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That sounds fine. Perhaps double check the power supply is putting out 3.3V. This is the maximum rating of the raspberry pi GPIO pins.


Is it possible that a TFT display being used?
Github has something about it for a Pi4 here.

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no display at all.

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