pi zero w does not respond

Question

Ordered a Pi Zero w, arrived, but I did not check it before I soldered the 40 pin GPIO onto it. Now it does not seem to be starting at all.

I visually inspected the solders, they are not touching each other, then I checked for short circuit with multimeter, does not seem to have any short circuits.

Then I tried plugging everything I plugged into a working Pi 3B onto it (including the SD card, power, touch screen with HDMI and GPIO connection), no respond at all. no lights.

Then I tried to only plug in the power and SD card, no respond at all, no lights.

Is there anything else I can do to check the board? Could the soldering process have destroyed it with heat (I am not that good with solder)?

I don't want to return to seller, as it crossed continents to arrive in Asia, its not cost efficient to return.

Answer 1

The most basic check is to leave out any mSD card, and then to power up your Pi Zero W. It doesn't matter if your power through the power-only micro USB socket or backpower through the OTG/slave USB micro socket: both will be fine for such tests. If on power on you don't see the green ACT LED lighting up and shortly blinking, your Pi Zero W is pretty much dead.

Check your soldering for any unwanted solder bridges or solder blobs that went to places where they should not be.

As every Pi gets fully factory tested, there is a very low chance that your Pi arrived dead. There have been few cases of wrongly programmed OTP fuses, but that's not the case here.

Please note that with the Pi Zero W the meaning of the ACT LED has been reversed from it's meaning on the 3B: this allows the single ACT LED to also, erm, act as a PWR LED. So normally it should be lit. Only when there are mSD card read/write, ACT starts to blink or going dark if there are extensive read/writes; but usually only for two or three seconds at most.