Oil pressure

Hi all. Back again.
Range rover vogue l322 td6 05 plate
Iv had a stop engine press I assume it means pressure. Doesn't say high or low and flashes and goes away. Car drives fine. First point was gonna be oil change and fillter. Was also gonna change the pressure switch while I was at it. But I carnt find any information or location for the switch. Any advice would be much appreciated.

Oil pressure switch should be on the backside of the filter housing body on that , the m57 engine can suffer with oil pump or turbo issues if it hasn't been serviced properly but pressure sensor is certainly the cheapest and easiest to sort

So did a oil service changed switch and all is good. So far.