Zumo Shield 1.2 problem with motors

Hi everyone!

Just after soldering and assembling my Zumo robot following the instructuions and plugging into my computer I tried to run the ZumoMotorExample from the official libraries with no success, the lead pin is blinking well but the motors do not move at all, I tried to connect an external led to pins 7, 8, 9, 10 to test the levels and it seems to work fine, the led is gradually fading as expected when tested on pins 9 and 10, and blinking when connected to pins 7 and 8. I tested also the switch button by swapping on and off, nothing happens; finally I tested with the led the wires to the motors and seems to be no voltage there.

Why the motors are not moving?, must I use batteries instead the USB connection?

Please I need some help, thank you.


The motors are powered from the batteries, so you will need batteries to test them.