BCM : Diagnosis Procedure

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

1. CHECK FUSES AND FUSIBLE LINK

   Check that the following fuses and fusible link are not blown.

   FUSES AND FUSIBLE LINK REFERENCE
   
   

   Terminal No.	Signal name	Fuses and fusible link No.
   57	Battery power supply	18 (10A)
   70		G (50A)
   11	Ignition ACC or ON	4 (10A)
   38	Ignition ON or START	1 (10A)

   Is the fuse blown? 

   YES: Replace the blown fuse or fusible link after repairing the affected circuit.

   NO: GO TO  2

2. CHECK POWER SUPPLY CIRCUIT
   1. Turn ignition switch OFF.
   2. Disconnect BCM.
   3. Check voltage between BCM harness connector and ground.
      VOLTAGE SPECIFICATION
      
      

      Connector	Terminals		Power source	Condition	Voltage (V) (Approx.)
      	(+)	(-)
      M18	11	Ground	ACC power supply	Ignition switch ACC or ON	Battery voltage
      	38	Ground	Ignition power supply	Ignition switch ON or START	Battery voltage
      M20	57	Ground	Battery power supply	Ignition switch OFF	Battery voltage
      	70	Ground	Battery power supply	Ignition switch OFF	Battery voltage

      Fig 1: Checking Voltage Between BCM Connector Terminals 11, 38, 57, 70 And Ground

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

      Is the measurement value normal? 

      YES: GO TO  3

      NO: Repair or replace harness.

3. CHECK GROUND CIRCUIT

   Check continuity between BCM harness connector and ground.

   CONTINUITY SPECIFICATION
   
   

   BCM		Ground	Continuity
   Connector	Terminal
   M20	67		Yes

   Does continuity exist? 

   YES: Inspection End.

   NO: Repair or replace harness.

   Fig 2: Checking Continuity Between BCM Connector M20 Terminal 67 And Ground

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