Rear Window Defogger Power Supply Circuit Check

WARNING: This page is about a different car, the 2005 Infiniti FX45 and 2005 Infiniti FX35. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FUSE
- Check 10A fuse [No.12, located in the 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 out, be sure to eliminate cause of malfunction before installing new fuse, refer to "POWER SUPPLY ROUTING CIRCUIT ".
CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Remove rear window defogger relay.
3. Turn ignition switch ON.
4. Check voltage between rear window defogger relay connector E13 terminals 1, 3, 6 and ground.
  1. 1 (OR) - Ground: Battery voltage
  2. 3 (W) - Ground: Battery voltage
  3. 6 (R) - Ground: Battery voltage
OK or NG
1. OK: GO TO 3.
2. NG: Repair or replace harness.
Fig 1: Checking Voltage Between Rear Window Defogger Relay Connector E13 Terminals 1, 3, 6 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK REAR WINDOW DEFOGGER RELAY
Check continuity between rear window defogger terminals 3 and 5, 6 and 7.

Fig 2: Terminal Continuity Chart
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 3: 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. Turn ignition switch OFF.
2. Installation rear window defogger relay.
3. Turn ignition switch ON.
4. Check voltage between IPDM E/R connector and ground.
  
  Fig 4: Connector Terminal Wire Color Specification
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 5: Checking Voltage Between IPDM E/R Connector And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: Rear window defogger power supply circuit is OK.
2. NG: GO TO 5.
CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and rear window defogger relay.
3. Check continuity between IPDM E/R connector E9 terminal 52 and rear window defogger relay connector E13 terminal 2.
  1. 52 (G) - 2 (G): Continuity should exist.
OK or NG
1. OK: GO TO 6.
2. NG: Repair or replace harness.
Fig 6: Checking Harness Continuity
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK REAR WINDOW DEFOGGER RELAY OUTPUT SIGNAL
1. Connect IPDM E/R connector and rear window defogger relay.
2. Turn ignition switch ON.
3. Check voltage between IPDM E/R connector E9 terminal 52 and ground.
  1. 52 (G) - Ground: Battery voltage
OK or NG
1. OK: Check condition of harness and connector.
2. NG: Replace IPDM E/R.
Fig 7: Checking Voltage Between IPDM E/R Connector E9 Terminal 52 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.