Diagnosis Procedure

WARNING: This page is about a different car, the 2020 Infiniti QX60. However, it is still accessible from the selected car via links, so may be relevant.

CHECK DTC PRIORITY
If DTC U042F is displayed with DTC U1000, first perform the confirmation procedure (trouble diagnosis) for DTC U1000.

Is DTC U1000 detected?

YES

Perform diagnosis for U1000. Refer to DTC Description .

NO

GO TO 2.

CHECK ENGINE COMMUNICATION CIRCUIT

Turn ignition switch OFF.
Disconnect ECM harness connector and electric intake valve timing (IVT) control module harness connector.

Check the continuity between ECM harness connector and electric IVT control module harness connector.

ECM		Electric IVT control module		Continuity
Connector	Terminal	Connector	Terminal
E32	189	F105	25	Existed
	190		24

Check harness for short to power and short to ground.

Is the inspection result normal?

YES

GO TO 3.

Repair or replace error-detected parts.

CHECK INTERMITTENT INCIDENT
Check intermittent incident. Refer to Intermittent Incident .

Is the inspection result normal?

YES

Replace electric IVT control module. Refer to Removal and Installation .

NO

Repair or replace error-detected parts.