Crankshaft position sensor circuit a help!!

I have a 2012 micra and on diagnostic it's saying crankshaft position sensor circuit A. Where abouts is this located to replace it. Mechanic can't find it and I'm not sure if I have the right part or not. Many thanks
Is it HR12DE or DIG-S?

On Note E12 (the same engines as K13), the problem is often not due to that sensor but because of dirty oil and/or IVVT solenoid got stuck.

The crank position sensor on these cars is a little odd as it runs off the flywheel so it is positioned in the bell housing for the gearbox. With the bonnet open it is positioned in the middle front area of the engine bay, might be below the airbox as I've removed mine so can't tell if it is. Hopefully this makes sense.

Hope this helps