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 ON 

REAR DEF SW: ON 

When ignition switch is turned ON 

IGN ON SW: ON 

Fig 1: Consult-II Display - Data Monitor

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

With out CONSULT-II 

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

OK or NG 

OK:  Rear window defogger switch check is OK.

NG:  GO TO 2.

Fig 2: Identifying Voltage Between BCM Connector Ground

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

1. Turn ignition switch OFF.
2. Disconnect BCM and unified meter and A/C amp.
3. Check continuity between BCM connector M18 terminal 9 and unified meter and A/C amp. connector M89 terminal 38.

   9 - 38: Continuity should exist  .

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

   9 - Ground: Continuity should not exist  .

OK or NG 

OK:  GO TO 3.

NG:  Repair or replace harness.

Fig 3: Identifying Continuity Between BCM Connector M18 Terminal 9 And Ground

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

1. Connect BCM.
2. Turn ignition switch ON.
3. Check voltage between BCM connector M18 terminal 9 and ground.

   9 - Ground: Approx. 5V 

OK or NG 

OK:  Replace unified meter and A/C amp. Refer to "UNIFIED METER AND A/C AMP. ".

NG:  Replace BCM. Refer to "BCM ".

Fig 4: Identifying Voltage Between BCM Connector M18 Terminal 9 And Ground

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