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Check Rear Window Defogger Switch Circuit

CHECK REAR WINDOW DEFOGGER SWITCH OPERATION

With CONSULT-III

Check ("REAR DEF SW", "IGN ON SW") in DATA MONITOR mode with CONSULT-III.

When rear window defogger switch is turned to ON

REAR DEF SW : ON

When ignition switch is turned to ON

IGN ON SW : ON

Without CONSULT-III

Turn ignition switch ON.
Check voltage between BCM connector ground.

Fig 1: Identifying Voltage Between BCM Connector Ground

G04877429

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

REAR WINDOW DEFOGGER SWITCH OPERATION

Connector	Terminal (Wire color)		Condition	Voltage (V) (Approx.)
Connector	(+)	(-)	Condition	Voltage (V) (Approx.)
M3	9 (L/W)	Ground	Rear window defogger switch is pressed.	0
M3	9 (L/W)	Ground	Rear window defogger switch is OFF.	5

OK or NG

OK: Rear window defogger switch is OK.

NG: GO TO 2.

CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect BCM and A/C and AV switch connector.
3. Check continuity between BCM connector M3 terminal 9 and A/C and AV switch connector M64 terminal 16.
  9 (L/W) - 16 (L/W) : Continuity should exist.
  
  Fig 2: Identifying Continuity Between BCM Connector M3 Terminal 9 And A/C And AV Switch Connector M64 Terminal 16
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK: GO TO 3.

NG: Repair or replace harness.
CHECK BCM OUTPUT SIGNAL
1. Connect BCM connector.
2. Turn ignition switch ON.
3. Check voltage between BCM connector M3 terminal 9 and ground.
  9 (L/W) - Ground : Approx. 5
  
  Fig 3: Identifying Voltage Between BCM Connector M3 Terminal 9 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK: Replace A/C and AV switch.

NG: Replace BCM.