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 engine speed was 50 RPM below governed idle speed for 30 seconds.

DTC	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
P050A-00	ISC SYSTEM (Idle Air Control System RPM Lower Than Expected)	Diagnosis condition	Engine running at idle.
		Signal (terminal)	(-)
		Threshold	Engine speed - idle reference speed > 50 RPM, when the amount of time that engine speed is outside the idle reference speed band, by more than 50 RPM, is equal to 15 seconds Coolant is 10 degrees Celsius (50 degrees Fahrenheit)
		Diagnosis delay time	Diagnostic runs continuously when the engine is running