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Home >> Lexus >> 2008 >> RX 400h FWD >> Repair and Diagnosis (Single Page) >> Body & Frame >> Windows >> Windshield/WINDOWGLASS >> Window Defogger System >> Rear Window Defogger System does not Operate >> Inspection Procedure
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Inspection Procedure

  1. INSPECT COMMUNICATION LINE 
    1. Use Techstream to check for normal function of the multiplex communication system.
      1. (ECU unconnected, communication line malfunctioning) Without DTC B1214, B1215 or B 1262 outputs, proceed to A.
      2. (ECU unconnected, communication line malfunctioning) With DTC B1214, B1215 or B 1262 outputs, proceed to B.

    B:  Go to MULTIPLEX COMMUNICATION SYSTEM

    A: Go to next step 

  2. INSPECT FUSE (HEATER, RR-DEF) 
    1. Remove the HEATER fuse from the instrument panel J/ B.
    2. Remove the RR-DEF fuse from the FL block.
    3. Check the resistance.

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  3. PERFORM ACTIVE TEST 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch on.
    3. Perform the Active Test according to the display on the tester.

      AIR CONDITIONER: 

      AIR CONDITIONER REFERENCE CHART

      Tester Display Test Part Control Range Diagnostic Note
      Defogger Relay Operate rear window defogger OFF/ON -

    NG: Go to step  5

    OK: Go to next step 

  4. CHECK AIR CONDITIONING SYSTEM OPERATE 

    NG:  GO TO AIR CONDITIONING SYSTEM

    OK: REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 

  5. INSPECT JUNCTION BLOCK 
    1. Check the voltage of the terminal of the J/B.
      Fig 1: Identifying 2H And 2B Connector Terminals
      G05205142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Switch Position Specified Condition
      2H-12 - Body Ground Ignition switch ON 10 to 14 V
      2H-12 - Body Ground Ignition switch OFF Below 1 V
      2B-8 - Body Ground Always 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    OK: Go to next step 

  6. INSPECT JUNCTION BLOCK (MODE MONITOR TERMINAL) 
    1. Check the voltage of the terminal to the following condition.
      • Engine running.
      • A/C switch is OFF.
      • Rear defogger and deicer switch is ON.

        Result 

        RESULT CHART

        Result Proceed to
        More than 5 V A
        Below 2 V B
        • Fig 2: Identifying Mode Monitor Terminal
        G05205143Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: Go to step  12

    A: Go to next step 

  7. INSPECT JUNCTION BLOCK (RR-DEF RELAY) 
    1. Remove the junction block No.2.
    2. Connect the battery positive (+) lead to terminal 2B-8 and battery negative (-) terminal lead to terminal 2H-12, 2B-7 and 2H-11.
    3. Check the voltage of the RR-DEF relay terminals.
      Fig 3: Identifying 2H And 2B Connector Terminals
      G05205142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      2B-7 - 2H-13 Always Below 1 V
    4. Connect another battery positive (+) lead to the terminal 2H-12.
    5. Check the voltage of the RR-DEF relay terminals.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      2B-7 - 2H-13 Ignition switch ON Below 1 V
      2B-7 - 2H-13 Ignition switch OFF 10 to 14 V

    NG: REPLACE JUNCTION BLOCK 

    OK: Go to next step 

  8. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Disconnect the A8 connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester connection Condition Specified condition
      A8-19 (DFG) - Body ground Ignition switch: ON 10 to 14 V
      A8-19 (DFG) - Body ground Ignition switch: OFF Below 1 V
      3. Fig 4: Disconnecting A8 Connector
      G05864115Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Connect the A8 connector.
    2. Connect Techstream to the DLC3.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester connection Techstream condition Specified condition
      A8-19 (DFG) - Body ground Active Test: ON (*1) 10 to 14 V
      A8-19 (DFG) - Body ground Active Test: OFF (*1) Below 1 V
      HINT:
      *1: Perform the Active Test according to the display on the tester.
      Fig 5: Connecting A8 Connector
      G05864116Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      AIR CONDITIONER: 

      AIR CONDITIONER REFERENCE CHART

      Item Test Details Diagnostic Note
      DEFOGGER RLY-R Operate rear window defogger OFF/ON -

    NG: REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 

    OK: Go to next step 

  10. INSPECT REAR WINDOW DEFOGGER WIRE 
    NOTE:
    • When cleaning the glass, wipe the glass along the wire using a soft and dry cloth. Take care not to damage the wires.
    • Do not use detergents or glass cleaners that have abrasive ingredients.
    • When measuring voltage, wrap a piece of tin foil around the tip of the negative tester probe and press the foil against the wire with your finger, as shown in the illustration.
      Fig 6: Pressing Tin Foil
      G04967166Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch on.
    2. Turn the defogger switch ON.
      Fig 7: Checking Rear Window Defogger Wire
      G04967167Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the voltage at the center of each defogger wire, as shown in the illustration.

      Standard voltage 

      VOLTAGE REFERENCE CHART

      Voltage Criteria
      Approx .5 V Wire is not broken
      Approx. 10 or 0 V Wire is broken

      HINT:

      If there is approximately 10 V, the wire may be broken between the center of the wire and the wire end on the battery side. If there is no voltage, the wire may be broken between the center of the wire and the end on the ground side.

      Fig 8: Checking Voltage Center Of Defogger Wire
      G04833939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Place the voltmeter positive (+) lead against the defogger wire on the battery side.
    5. Place the voltmeter negative (-) lead with the foil strip against the wire on the ground side.
    6. Slide the positive (+) lead from the battery side to the ground side.
    7. The point where the voltage drops from approximately 10 V to 0 V is where the defogger wire is broken.

      HINT:

      If the defogger wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the defogger wire but gradually increases to approximately 12 V as the meter probe moves to the other end.

    NG: REPAIR REAR WINDOW DEFOGGER WIRE 

    OK: Go to next step 

  11. CHECK WIRE HARNESS (REAR WINDOW DEFOGGER - JUNCTION BLOCK NO.2) 
    1. Disconnect the N4, N5 defogger and 2B J/B connectors.
    2. Check the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      N4-1 - 2B-7 Below 1 Ω
      N4-1 - Body ground 10 kΩ or higher
      NS-1 - Body ground Below 1 Ω
      N5-1 - 2B-7 10 kΩ or higher
      3. Fig 9: Identifying N4, N5 Defogger And 2B J/B Connector Terminals
      G05281146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE NOISE FILTER 

  12. CHECK WIRE HARNESS (REAR WINDOW DEFOGGER - JUNCTION BLOCK NO.2) 
    1. Disconnect the N4, N5 defogger and 2B J/B connectors.
    2. Check the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      N4-1 - 2B-7 Below 1 Ω
      N4-1 - Body ground 10 kΩ or higher
      N5-1 - Body ground Below 1 Ω
      N5-1 - 2B-7 10 kΩ or higher
      3. Fig 10: Identifying N4, N5 Defogger And 2B J/B Connector Terminals
      G05281146Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  13. INSPECT JUNCTION BLOCK (RR-DEF RELAY) 
    1. Remove the junction block No.2.
    2. Connect the battery positive (+) lead to terminal 2B-8 and battery negative (-) terminal lead to terminal 2H-12, 2B-7 and 2H-11.
    3. Check the voltage of the RR-DEF relay terminals.
      Fig 11: Identifying 2H And 2B Connector Terminals
      G05205142Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      2B-7 - 2H-12 Always Below 1 V
    4. Connect another battery positive (+) lead to the terminal 2H-12.
    5. Check the voltage of the RR-DEF relay terminals.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      2B-7 - 2H-12 Ignition switch ON 10 to 14 V
      2B-7 - 2H-12 Ignition switch OFF Below 1 V

    NG: REPLACE JUNCTION BLOCK 

    OK: REPLACE NOISE FILTER 

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