you have to look at the spec of your board, i think it might say something if it requires you to ground any pins.
actually first thing you should try is to read the who am i register
do sth like:
wire.beginTransmission(address);
wire.write(who_am_i_reg)
wire.endTransmission();
wire.requestFrom(address,1);
Serial.pring(wire.read());
there should be a default value for the register just check that up first