Rear Window Defogger Power Supply Circuit Check

WARNING: This page is about a different car, the 2005 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FUSE
Check 10A fuse [No.12, located in fuse block (J/B)]

Check 20A fuse [No.75, located in the IPDM E/R]

Check 20A fuse [No.80, located in the IPDM E/R]

NOTE: Refer to "Component Parts and Harness Connector Location ".

OK or NG
1. OK: GO TO 2.
2. NG: If fuse is blown, be sure to eliminate cause of malfunction before installing new fuse, refer to POWER SUPPLY ROUTING CIRCUIT .
CHECK REAR WINDOW DEFOGGER RELAY POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear window defogger relay.
3. Check voltage between rear window defogger relay connector and ground.
  
  Fig 1: Voltage Check Between Rear Window Defogger Relay Connector And Ground Table
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 2: Checking Voltage Between Rear Window Defogger Relay Connector And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 3.
2. NG: Repair or replace harness.
CHECK REAR WINDOW DEFOGGER RELAY
Check continuity between rear window defogger terminals 3 and 5, 6 and 7.

Fig 3: Continuity Check Between Rear Window Defogger Terminals 3 And 5, 6 And 7 Table
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 4: Checking Continuity Between Rear Window Defogger Terminals 3 And 5, 6 And 7
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 4.
2. NG: Replace rear window defogger relay.
CHECK REAR WINDOW DEFOGGER RELAY GROUND CIRCUIT
1. Installation rear window defogger relay.
2. Turn ignition switch ON.
3. Turn rear window defogger switch OFF.
4. Check voltage between IPDM E/R connector E9 terminal 52 and ground.
  52 (G/R) - Ground: Battery voltage
OK or NG
1. OK: Rear window defogger power supply circuit check is OK.
2. NG: GO TO 5.
  
  Fig 5: Checking Voltage Between IPDM E/R Connector E9 Terminal 52 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK IPDM E/R HARNESS
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and rear defogger relay.
3. Check continuity between IPDM E/R connector E9 terminal 52 and rear window defogger relay connector B109 terminal 2.
  52 (G/R) - 2 (G/R): Continuity should exist.
OK or NG
1. OK: Check the connector for damage and loose connection.
2. NG: Repair or replace harness.
  
  Fig 6: Checking Continuity Between IPDM E/R Connector E9 Terminal 52 And Rear Window Defogger Relay Connector B109 Terminal 2
  Courtesy of NISSAN MOTOR CO., U.S.A.