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 fuse IPDM E/R]
- Check 20A fuse [No. 80, located in fuse 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. Turn ignition switch ON.
4. Check voltage between rear window defogger relay connector B417 terminal 1, 3, 6 and ground.
  
  Fig 1: Rear Window Defogger Relay Connector B417 Terminal & Ground Voltage Chart
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 2: Checking Voltage Between Rear Window Defogger Relay Connector B417 Terminal 1, 3, 6 & 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: Rear Window Defogger Terminals Continuity Chart
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 4: Checking Continuity Between Rear Window Defogger Terminals
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. Turn ignition switch OFF.
2. Installation rear window defogger relay.
3. Turn ignition switch ON.
4. Turn rear window defogger switch OFF.
5. 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 & 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 B417 terminal 2.
  52 (G/R) - 2 (BR): Continuity should exist.
OK or NG
1. OK: Check connector for damage and loose connection.
2. NG: Repair or replace harness.
Fig 6: Checking Continuity Between IPDM E/R Connector Terminal 52 & Rear Window Defogger Relay Connector Terminal 2
Courtesy of NISSAN MOTOR CO., U.S.A.