Diagnosis Procedure

WARNING: This page is about a different car, the 2013 Nissan Armada. However, it is still accessible from the selected car via links, so may be relevant.

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM ".

CHECK FUSE
Check if the key switch and ignition knob switch (key switch) 10A fuse (No. 62, located in the fuse and relay box) is blown.

Is the fuse blown?

YES: Be sure to repair the cause of malfunction before installing new fuse.

NO: GO TO 2

CHECK BCM INPUT SIGNAL

Check voltage between BCM harness connector M18 terminal 37 and ground.

Terminals			Condition	Voltage (Approx.)
(+)		(-)
BCM connector	Terminal	(-)
M18	37	Ground	Key is inserted	Battery voltage
M18	37	Ground	Key is removed	0

Fig 1: Checking Voltage Between BCM Connector M18 Terminal 37 And Ground

Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES: Inspection End.

NO: GO TO 3

CHECK KEY SWITCH AND IGNITION KNOB SWITCH (KEY SWITCH) CIRCUIT

Disconnect BCM connector M18 and key switch and ignition knob switch (key switch).

Check continuity between BCM harness connector M18 (A) terminal 37 and key switch and ignition knob switch (key switch) harness connector M12 (B) terminal 4.

BCM		Key switch and ignition knob switch (key switch)		Continuity
Connector	Terminal	Connector	Terminal	Continuity
M18 (A)	37	M12 (B)	4	Yes

Fig 2: Checking Continuity Between BCM Connector M18 Terminal 37 And Key Switch And Ignition Knob Switch Connector M12 Terminal 4

Courtesy of NISSAN NORTH AMERICA, INC.

Check continuity between BCM harness connector M18 (A) terminal 37 and ground.

BCM		Ground	Continuity
Connector	Terminal
M18 (A)	37		No

Is the inspection result normal?

YES: GO TO 4

NO: Repair or replace harness.

CHECK KEY SWITCH AND IGNITION KNOB SWITCH (KEY SWITCH) POWER SUPPLY CIRCUIT

Check voltage between key switch and ignition knob switch (key switch) harness connector M12 terminal 3 and ground.

Terminals			Voltage (Approx.)
(+)		(-)
Key switch and ignition knob switch (key switch) connector	Terminal	(-)
M12	3	Ground	Battery voltage

Fig 3: Checking Voltage Between Key Switch And Ignition Knob Switch (Key Switch) Connector M12 Terminal 3 And Ground

Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES: Replace key switch and ignition knob switch (key switch).

NO: Repair or replace harness.