Problem with ITG/MPU GY-521 6 DOF acc & gyro not working

I am trying to connect GY-521 to Arduino UNO board with the following setup :

VCC - 5V GND - GND SCL - A5 pin SDA - A4 pin

However, I cannot make a connection between GY-521 and UNO board.

I,ve tried to seach the error with I2cScanner program, but gives the following result :

I2C Scanner Scanning...

Using Gy521_send_serial or GY-521-Dev-Kit (https://github.com/janaka/Gy521-Dev-Kit), before calling endTransmission(), the Serial print works well. However, after calling endTransmission(), the Serial print doesn't work at all. The printed result is

InvenSense MPU-6050 June 2012

Please let me know why the GY-521 doesn't give any reponse after calling endTransmission(). Is there anybody who experience the similar situations?