Good day, I have a 2018 Nissan Frontier 2.5l NP300, 60 000km on the clock. it keeps going into limp mode when I reach 3000rpm. the only error I get is P012B. can this cause the limp mode and how can I fix it?

We tried replacing the Solenoid Control Valve on the pump
Replaced the Pressure Release Valve

Any and all advice will be appreciated!

Unfortunately, we don't have the 2.5 diesel engine in the US. The P012B code can be triggered by the following:

-Faulty Turbocharger/Supercharger Inlet Pressure Sensor
-Turbocharger/Supercharger Inlet Pressure Sensor harness is open or shorted
-Turbocharger/Supercharger Inlet Pressure Sensor circuit poor electrical connection

Read more: P012B Turbocharger/Supercharger Inlet Pressure Sensor Circuit Range/Performance Downstream Of Throttle Valve (https://www.autocodes.com/p012b.html)

I would believe that it could cause you to go into limp mode. I did find that there are several YouTube videos that have diagnostic information pertaining to this code for this application, so that would be a good place to start. You should check the harness connections in the circuit to make sure the pins are clean, straight and not pushed out of the connector. Ideally, a factory service manual should be accessed where you can find the step-by-step diagnostics for that particular code along with the wiring diagrams, but I don't know of any places to access FSM's for vehicles outside of the US.