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 - WITH INTELLIGENT KEY SYSTEM ".

CHECK KEY SWITCH POWER SUPPLY CIRCUIT
1. Remove mechanical key from ignition switch.
2. Disconnect key switch and ignition knob switch connector.
3. Check voltage between key switch and ignition knob switch harness connector M12 terminal 3 and ground.
  3 - Ground: Battery voltage.
  
  Fig 1: Checking Key Switch Power Supply Circuit Voltage
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  Is the inspection result normal?
  
  YES: GO TO 2
  
  NO: Check harness between key switch and ignition knob switch and fuse.

CHECK KEY SWITCH

Check continuity between key switch and ignition knob switch terminals 3 and 4.

Component	Terminals		Condition	Continuity
Ignition switch	3	4	Insert mechanical key into ignition switch.	Yes
Ignition switch	3	4	Remove mechanical key from ignition switch.	No

Fig 2: Checking Continuity Between Key Switch And Ignition Knob Switch Terminals 3 & 4

Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES: GO TO 3

NO: Replace key cylinder assembly (built-in key switch).

CHECK KEY SWITCH SIGNAL CIRCUIT
1. Disconnect BCM connector.
2. Check continuity between BCM harness connector M18 terminal 37 and key switch and ignition knob switch harness connector M12 terminal 4.
  37 - 4: Continuity should exist.
3. Check continuity between BCM harness connector M18 terminal 37 and ground.
  37 - Ground: Continuity should not exist.
  
  Fig 3: Checking Key Switch Signal Circuit Continuity
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  Is the inspection result normal?
  
  YES: Key switch (BCM input) circuit is OK.
  
  NO: Repair or replace harness between key switch and ignition knob switch and BCM.