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: DATA MONITOR - CONSULT-II Display Screen

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

With out CONSULT-II 

1. Turn ignition switch ON.
2. Check voltage between BCM connector ground.
   Fig 2: Terminals Voltage Reference Chart

   Courtesy of NISSAN MOTOR CO., U.S.A.
   Fig 3: Checking Voltage Between BCM Connector Ground

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

OK or NG

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

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 (W) - 38 (W): Continuity should exist  .

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

   9 (W) - Ground: Continuity should not exist  .

OK or NG

• OK: GO TO  3.
• NG: Repair or replace harness.
  Fig 4: Checking Rear Window Defogger Switch Circuit Harness Continuity

  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 (W) - Ground: Approx. 5 

OK or NG

• OK: Replace unified meter and A/C amp. Refer to UNIFIED METER AND A/C AMP .
• NG: Replace BCM. Refer to REMOVAL AND INSTALLATION OF BCM .
  Fig 5: Checking BCM Output Signal

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