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Check Key Switch (BCM Input)

CHECK KEY SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition knob OFF position.
2. Disconnect key switch and ignition knob switch connector.
3. Check voltage between key switch and ignition knob switch connector M22 terminal 3 (L/R) and ground.
  3 (L/R) - Ground : Battery voltage.
  
  Fig 1: Identifying Voltage Between Key Switch And Ignition Knob Switch Connector M22 Terminal 3 (L/R) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK: GO TO 2.

NG: Check harness between key switch and ignition knob switch and fuse.

CHECK KEY SWITCH

Check continuity between key switch and ignition knob switch as follows.

Fig 2: Identifying Continuity Between Key Switch And Ignition Knob Switch Connector Terminals 3 And 4

G04916738

Courtesy of NISSAN MOTOR CO., U.S.A.

KEY SWITCH

Terminals		Condition	Continuity
3	4	Key is inserted in ignition key cylinder.	Yes
3	4	Key is removed from ignition key cylinder.	No

OK or NG

OK: GO TO 3.

NG: Replace key switch and ignition knob switch.

CHECK KEY SWITCH SIGNAL CIRCUIT
1. Disconnect key switch and ignition knob switch connector and BCM connector.
2. Check continuity between key switch and ignition knob switch connector M22 terminal 4 (B/W) and BCM connector M3 terminal 37 (B/W).
  4 (B/W) - 37 (B/W) : Continuity should exist.
3. Check continuity between key switch and ignition knob switch connector M22 terminal 4 (B/W) and ground.
  4 (B/W) - Ground : Continuity should not exist.
  
  Fig 3: Identifying Continuity Between Key Switch And Ignition Knob Switch Connector M22 Terminal 4 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK: Key switch (BCM input) circuit is OK.

NG: Repair or replace harness between key switch and ignition knob switch and BCM.

Press ignition knob. : ON

Return ignition knob (release hands from ignition knob) : OFF