Zumo 32U4 Not Working

My son and I just completed building our second Zumo 32U4. The first was completed without any problems and works fine.
We’re having problems with the second one. When we power it up, the display shows “Zumo 32U4” and the amber light flashes.
No sound is heard on boot up nor does it go into demo mode.

I checked all the solder connections and everything is good, no cold joints or solder bridges. I am stumped.

My son will be entering both these robots into a STEM competition at his school in a couple weeks, so we need to fix this problem as soon as



I connected the Zumo to my laptop and Arduino 1.6.5, the program recognized it
on COM3. I successfully loaded the Demo script, disconnected it, powered it off
then on. I immediately got the startup sound and it went into demo mode. I loaded
a series of other scripts and they all worked fine.

I thrilled that it now works, but still don’t know why it happened.


I am glad you were able to get your Zumo running. Thank you for letting us know what you did.