MKR 1400 modem died?

Hardware MKR Family MKRGSM1400
4

Try this sketch. It allows you to pass modem commands directly from the serial interface. Be sure to set the serial interface to terminate with carriage return and newline or the AT commands will not be interpreted by the modem.

unsigned long baud = 9600;

void setup() {
  // reset the ublox module
  pinMode(GSM_RESETN, OUTPUT);
  digitalWrite(GSM_RESETN, HIGH);
  delay(100);
  digitalWrite(GSM_RESETN, LOW);

  Serial.begin(baud);
  SerialGSM.begin(baud);

}

void loop() {
  if (Serial.available()) {
    SerialGSM.write(Serial.read());
  }

  if (SerialGSM.available()) {
    Serial.write(SerialGSM.read());
  }
}