Rear Window Defogger Switch Circuit Check

WARNING: This page is about a different car, the 2005 Nissan 350Z. However, it is still accessible from the selected car via links, so may be relevant.

CHECK REAR WINDOW DEFOGGER SWITCH OPERATION
With CONSULT-II

Check ("REAR DEF SW" and "IGN ON SW") in DATA MONITOR mode with CONSULT-II. Refer to "DATA MONITOR ".
- When rear defogger switch is turned to ON
- REAR DEF SW: ON
- When ignition switch is turned to ON
- IGN ON SW: ON
Fig 1: Scan Tool 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.
  
  Fig 2: BCM Connector & Ground Voltage Specification Table
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 3: BCM Connector & Ground Voltage Test
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
- OK: Rear window defogger switch check is OK.
- NG: GO TO 2.
REAR WINDOW DEFOGGER SWITCH SIGNAL CIRCUIT HARNESS CONTINUITY INSPECTION
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp. connector.
3. Check continuity between BCM connector M90 terminal 9 and unified meter and A/C amp. connector M50 terminal 38.
  - 9 (L/R) - 38 (L/R): Continuity should exist
4. Check continuity between BCM harness connector M90 terminal 9 (L/R) and ground
  - 9 (L/R) - Ground: Continuity should not exist
  Fig 4: BCM Connector M90 Terminal 9 & Unified Meter & A/C Amp. Connector M50 Terminal 38 Continuity Test
  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 M90 terminal 9 and ground.
  - 9 (L/R) - Ground: Approx. 5V
OK or NG
- OK: Replace unified meter and A/C amp.
- NG: Replace BCM.
Fig 5: BCM Connector M90 Terminal 9 & Ground Voltage Test
Courtesy of NISSAN MOTOR CO., U.S.A.