try it exactly like this
a var byte
b var byte
c var byte

a=%10010001
b=%00000000
i2cread sda,scl,a,b,[c],NOCONNECT

what about now? in case nothing is working, be sure that the pins you're using from the PIC are set to digital and they are bidirectionnal : input and output.

Tell us which pic you're using and which pins are connected to sensor.

Also be sure that scl and sda are not reverted.