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Home >> Nissan-Datsun >> 2003 >> Sentra SE-R, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 1072 (Rear Window Defogger) >> Rear Window Defogger >> Rear Window Defogger Power Supply Circuit Check
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Rear Window Defogger Power Supply Circuit Check

WARNING: This page is about a different car, the 2004 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FUSE 
    FUSE CHECKING

    Check if any of the following fuses for fuse block (J/B) and IPDM E/R are blown.
    COMPONENT PARTS TERMINAL NO. (SIGNAL) AMPERE FUSE NO.
    Fuse block (J/B) 2T (Ignition power supply) 10A #12
    IPDM E/R 5 (Battery power supply) 20A #37
    6 (Battery power supply) 20A #32
    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  ".
  2. 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 and ground.
    REAR WINDOW DEFOGGER RELAY CONNECTORS VOLTAGE

    Connector Terminals (Wire color) Voltage (V)(Approx.)
    (+) (-)
    B4 (1L) Ground Battery voltage
    (3L)
    6(W)
    Fig 1: Checking Voltage Between Rear Window Defogger Relay Connector And Ground
    G03500219Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK: GO TO 3.
    2. NG: Repair or replace harness.
  3. CHECK REAR WINDOW DEFOGGER RELAY

    Check continuity between rear window defogger terminals 3 and 5, 6 and 7.

    REAR WINDOW DEFOGGER TERMINALS CONTINUITY

    Terminal Condition Continuity
    6 7 12V direct current supply between terminals 1 and 2 Yes
    No current supply No
    3 5 12V direct current supply between terminals 1 and 2 Yes
    No current supply No

    OK or NG

    1. OK: GO TO 4.
    2. NG: Replace rear window defogger relay.
    Fig 2: Checking Continuity Between Rear Window Defogger Terminals 3 And 5, 6 And 7
    G03500220Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK REAR WINDOW DEFOGGER RELAY GROUND CIRCUIT 
    1. Install rear window defogger relay.
    2. Turn ignition switch ON.
    3. Check voltage between IPDM E/R connector E121 and ground.
    IPDM E/R CONNECTORS VOLTAGE

    Connector Terminals (Wire color) Condition Voltage (V)(Approx.)
    (+) (-)
    E121 52 (G/R) Ground When rear window defogger switch ON 0
    When rear window defogger switch OFF Battery voltage
    Fig 3: Checking Voltage Between IPDM E/R Connector E121 And Ground
    G03500221Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK: Rear window defogger power supply circuit check is OK.
    2. NG: GO TO 5.
  5. CHECK IPDM E/R HARNESS 
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R and rear window defogger relay.
    3. Check continuity between IPDM E/R connector E121 terminal 52 and rear window defogger relay connector B4 terminal 2.
    1. 52 (G/R) - 2 (G/R): Continuity should exist. 

    OK or NG

    1. OK: GO TO 6.
    2. NG: Repair or replace harness.
    Fig 4: Checking Continuity Between IPDM E/R Connector E121 Terminal 52 And Rear Window Defogger Relay Connector B4 Terminal 2
    G03500222Courtesy of NISSAN MOTOR CO., U.S.A.
  6. CHECK REAR WINDOW DEFOGGER RELAY OUTPUT SIGNAL 
    1. Connect IPDM E/R and rear window defogger relay.
    2. Turn ignition switch ON.
    3. Check voltage between IPDM E/R connector E121 terminal 52 and ground.
    1. 52 (G/R) - Ground: Battery voltage 

    OK or NG

    1. OK: Replace IPDM E/R.
    2. NG: Repair or replace harness.
    Fig 5: Checking Voltage Between IPDM E/R Connector E121 Terminal 52 And Ground
    G03500223Courtesy of NISSAN MOTOR CO., U.S.A.
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