Try to power it on through the playstation. And make sure under accessory setting it is set as your input/output device.
REP IF IT WORKS!!!
apparently you can't power it on through PS3... But go to accessory setting> audio settings and make sure its set as your your input/output device. If so, turn your mic on and see if a blue light appears on screen. If it does then your mic is connected now. So if it still doesn't work but the light is on, the mic is broke. If the light doesn't appear, press triangle over the device and hit connect. If that doesn't work, its probably your mic.