Connections of fingerprint sensor module R307

Hey guys, I have been using fingerprint sensor module R307 using the tutorials present online and I am able to make projects using it. However, there are 6 pins on the sensor but all the tutorials use only 4 pins and leave the finger detection signal and finger detection power. I am not able to find out the use of these pins. Can someone help me with this so that I can save some battery using them? Thanks in advance.