DTC Detection Logic

WARNING: This page is about a different car, the 2018 Nissan Titan XD. However, it is still accessible from the selected car via links, so may be relevant.

The Engine Control Module (ECM) detected the fuel rail pressure was greater than 0.6V (key on) or less than 0.4V (key off)

NOTE: CONSULT displays fuel supply pressure as absolute pressure. Subtract 101 kPa (1.03 Kg/cm ² , 14.7 psi) at sea level from the CONSULT fuel supply pressure reading to approximate the gauge pressure reading.

DTC	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
P0191-00	FRP_SENSOR (Fuel Rail Pressure Sensor "A" Circuit Range/Performance)	1	Diagnosis condition	Ignition is turned ON and before engine speed is detected. Ignition OFF. The DTC will be active at the next ignition ON event.
			Signal (terminal)	Fuel rail pressure sensor (-)
			Threshold	Rail pressure sensor at ignition ON > 0.609V (59.965 bar absolute) Or The delay time after all enable conditions are satisfied is greater than a calculated threshold at ignition OFF and Rail pressure sensor at ignition OFF > 0.609V (59.965 bar absolute)
			Diagnosis delay time	Diagnostic runs continuously when the engine is running
		2	Diagnosis condition	Ignition is turned ON and before engine speed is detected. Ignition OFF. The DTC will be active at the next ignition ON event.
			Signal (terminal)	Fuel rail pressure sensor (171)
			Threshold	Rail pressure sensor at ignition ON < 0.424V (0 bar absolute) Or The delay tome after all enable conditions are satisfied is greater than a calculated threshold at ignition OFF and Rail pressure sensor at ignition OFF < 0.424V (0 bar absolute)
			Diagnosis delay time	Diagnostic runs continuously when the engine is running