Rear Window Defogger Switch Circuit Check

With CONSULT-II 

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

When rear window defogger switch is turned to ON 

REAR DEF SW : ON 

When ignition switch is turned to ON 

IGN ON SW : ON 

Fig 1: Identifying CONSULT-II Display - Data Monitor

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

Without CONSULT-II 

1. Turn ignition switch ON.
2. Check voltage between BCM connector and ground.
   Fig 2: Checking Voltage Between BCM Connector And Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.
   VOLTAGE BETWEEN BCM CONNECTOR AND GROUND REFERENCE
   
   

   Connector	Terminals		Condition	Voltage (V) (Approx.)
   	(+)	(-)
   M18	9 Y/B	Ground	Rear window defogger switch is pressed.	0
   			Rear window defogger switch is OFF.	5

OK or NG

• OK : Rear window defogger switch check is OK.
• NG : GO TO 2.

1. Turn ignition switch OFF.
2. Disconnect BCM and front air control.
3. Check continuity between BCM connector M18 terminal 9 and front air control connector M49 terminal 11.

   9 (Y/B) - 11 (Y/B) : Continuity should exist  .

4. Check continuity between BCM connector M18 terminal 9 and ground

   9 (Y/B) - Ground : Continuity should not exist  .

Fig 3: Checking Continuity Between BCM Connector M18 Terminal 9 And Front Air Control Connector M49 Terminal 11 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG

• OK : GO TO 3.
• NG : Repair or replace harness.

1. Connect BCM.
2. Turn ignition switch ON.
3. Check voltage between BCM connector M18 terminal 9 and ground.
   Fig 4: Checking Voltage Between BCM Connector M18 Terminal 9 And Ground

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

   9 (Y/B) - Ground : Approx. 5 

OK or NG

• OK : Replace front air control. Refer to "CONTROL UNIT ".
• NG : Replace BCM. Refer to "REMOVAL AND INSTALLATION OF BCM ".