how do i mend my crankshaft sensor on a renault megane?

hi,i changed mine on r reg megane yesterday,as u look at engine,on the right hand side down the bottom on the side of the engine u will c the sensor held on by 2 10 mm bolts and a wire coming out of it and going 2 a connection,simply dissconnect it from power first,then undo the 2 bolts pull out and replace,do bolts up 1st then reconnect 2 power,unfortunately after i had replaced mine it still did not start :(
i have a question under the title " is it the renault immobiliser" .
mark

mark
June 2007