Check the usual suspects: Is the I²C bus initialised? Wire.begin(); Does the I²C device run at 3.3V? Otherwise, use a logic-level converter. Are pull-ups installed? Try 10, 4.7 or 2.2 kΩ for the SDA and SCL lines. In case the LaunchPad provides multiple I²C ports, is the correct port selected? Try  Wire.setModule(0); // or other port number Wire.begin(); Still nothing? Use a logic analyser to trace the signals on the I²C port.