Rear Window Defogger Power Supply Circuit Check

WARNING: This page is about a different car, the 2003 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FUSE
Check if any of the following fuses for Fuse block (J/B) and IPDM E/R are blown.

Fig 1: Rear Window Defogger Power Supply Circuit Fuse Table
Courtesy of NISSAN MOTOR CO., U.S.A.

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 "COMPONENT PARTS AND HARNESS CONNECTOR LOCATION ".
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 B109 terminals 1, 3, 6 and ground.
Fig 2: Rear Window Defogger Relay Connector And Ground Voltage Table
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 3: 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 between fuse block (J/B) and rear window defogger relay.
CHECK REAR WINDOW DEFOGGER RELAY
Check continuity between rear window defogger terminals 3 and 5, 6 and 7.

Fig 4: Rear Window Defogger Terminals Continuity Table
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 5: 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. 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 54 and ground.
  1. 54 (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 6: Checking Voltage Between IPDM E/R Connector E9 Terminal 54 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 54 and rear window defogger relay connector B109 terminal 2.
  1. 54 (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 between IPDM E/R and rear window defogger relay.
Fig 7: Checking Continuity Between IPDM E/R Connector And Rear Window Defogger Relay Connector
Courtesy of NISSAN MOTOR CO., U.S.A.