2004 Volvo S60 map sensor

Manifold Pressure/Vacuum Sensor
7/81 Pressure Sensor, Intake Manifold

The manifold absolute pressure (MAP) sensor is in the intake hose for the throttle body (TB).

https://www.2carpros.com/kpages/auto_repair_manuals_alldata.htm

If you have a fuel pressure sensor code then I would recommend you call Volvo and give them your VIN # to see if there are any open recalls or campaigns related to the fuel pressure sensor. If there is one available and has not being done, Volvo will replace it at no charge too you. If your vehicle does not fall in there vin range the fuel pressure sensor is located on the fuel rail. I take it this is a turbo engine since you are asking about the map sensor, is also called the boost pressure sensor. Dont confuse it with the turbo control valve if you decide to order this from the dealer. Good luck and let me know how it goes.