Problem with: "Pololu dual vnh5019"

hi, my motor shield don’t work properly, It does not even work with the demo.
to the motor shield are connected an arduino uno and two pololu gearmotor, I supplied the driver shield with a 12V battery and the arduino from the computer.
when i start the demo on the serial monitor i have:

Dual VNH5019 Motor Shield
M1 fault
⸮e⸮

Any suggestions?

EDIT: i tried also a easier program
> .#include “DualVNH5019MotorShield.h”

DualVNH5019MotorShield md;

void stopIfFault()
{
if (md.getM1Fault())
{
Serial.println(“M1 fault”);
while (1);
}
if (md.getM2Fault())
{
Serial.println(“M2 fault”);
while (1);
}
}

void setup()
{
Serial.begin(115200);
Serial.println(“Dual VNH5019 Motor Shield”);
md.init();
}

void loop()
{
md.setM1Speed(400);
delay(300);
md.setM1Speed(0);
delay(300);
md.setM1Speed(400);
delay(300);
md.setM1Speed(0);
delay(300);
md.setM1Speed(400);
delay(300);
md.setM1Speed(0);
}

but nothing happens

Hello.

I am sorry you are having trouble getting your VNH5019 shield working. Can you post pictures that clearly show the soldered joints on your shield? Can you also verify that the baud rate on your Arduino IDE’s Serial Monitor is set to 115200?

-Jon