Hi hsuancho,
Could you please post the code you are using?
I found in the datasheet a recommended input for the LED input terminal. The Pulse Cycle should be 10ms, and the Pulse Width should be 0.32ms. The only difference I see between Galileo and Arduino UNO is the IO2 connection.
A quick test: try connecting the LED pin to the IO2 of the Arduino UNO instead to the IO2 of Galileo. The rest of the pins of the sensor are connected to 5V or GND, so keep them connected to 5V/GND pin of Galileo, just connected the LED pin to the IO2 of the UNO, and run the code in both boards.
Regards,
Diego.