How to solve the trouble code of Land Rover p0407 car?

The amount of exhaust gas in circuit b of the circulating valve sensor is low.

Exhaust gas recirculation sensor b circuit low.

Category: emission control/

Detailed meaning: The function of exhaust gas recirculation (EGR) system is to introduce a small amount of exhaust gas into the intake manifold when the engine is running at high load. The existence of these exhaust gases reduces the temperature and pressure of the combustion chamber, thus reducing the emission of nitrogen oxide pollutants. This fault code will occur if the electronic control unit (ECU) detects that the signal voltage of the exhaust gas recirculation (EGR) sensor is lower than the calibrated minimum value.