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Inspection Procedure

WARNING: This page is about a different car, the 2005 Lexus RX 330. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Start the inspection from step 1 when using the hand-held tester, and start from step 2 when not using the hand-held tester.

  1. PERFORM ACTIVE TEST USING HAND-HELD TESTER 
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch to ON position and press the hand-held tester main switch ON.
    3. Select the item below in the ACTIVE TEST and then check that the relay operates.

      BODY NO.1: 

      ITEM CONDITION CHART

      Item Test Details Diagnostic Note
      HEAD LIGHT Turn Headlight relay ON/OFF -
    1. NG: Go to step 2. 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    1. Disconnect the connector from the J/B No.2 (power distributor).
    2. Measure the voltage according to the value (s) in the table below.

      Standard: 

      TESTER SPECIFIED CONDITION CHART

      Tester connection Condition Specified value
      21 - 1 (+B) - Body ground Always 10 to 14 V
      Fig 1: Identifying Driver Side Junction Block Connector Terminals
      G03007440Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: Go to next step. 
  3. CHECK MODE MONITOR TERMINAL (H-LP R RELAY, H-LP L RELAY) 
    1. Preparation
      1. Connect the connector.
      2. Remove the cover of the fusible link block assy.
      3. Set the vehicle to the following condition.
        • Ignition switch ON.
        • Headlamp dimmer switch LO.
        • Light control switch ON.
    2. Check voltage
      1. Measure the voltage between the Mode Monitor Terminal and body ground.

        Result: 

        VOLTAGE REFERENCE CHART

        6.3 +/- 2 V A
        Approx. 1 V B
        Fig 2: Identifying Driver Side Junction Block Connector Terminals
        G03007441Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step  9 . 
    2. A: Go to next step. 
  4. INSPECT JUNCTION BLOCK NO.2 (HEADLAMP RELAY) 
    1. Turn the ignition switch to OFF position.
    2. Remove the J/B No.2.
    3. Inspect the H-LP R.
      Fig 3: Identifying Headlamp Connector Terminals
      G03007442Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Connect the positive battery lead to terminal +B of the J/B No.2 and the negative lead to terminal SGND, PGND.
        SYMBOL CONNECTION CHART

        Symbols (terminals No.) Connection
        +B (21-1) - SGND (2H-13), PGND (2F-1) Positive - Negative
      2. Measure the voltage according to the value (s) in the table below.

        Standard: 

        TESTER SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        LPR (2A-3) - Battery negative terminal Below 1 V
      3. Connect the battery negative lead to terminal HRLY of the J/B No.2.
        SYMBOL CONNECTION CHART

        Symbols (terminals No.) Connection
        HRLY (2H-8) Negative
      4. Measure the voltage according to the value (s) in the table below.

        Standard: 

        TESTER SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        LPR (2A-3) - Battery negative terminal 10 to 14 V
    4. Inspect the H-LP L.
      1. Connect the positive battery lead to terminal +B of the J/B No.2 and the negative lead to terminal SGND, PGND.
        SYMBOL CONNECTION CHART

        Symbols (terminals No.) Connection
        +B (2I-1) - SGND (2H-13), PGND (2F-1) Positive - Negative
      2. Measure the voltage according to the value (s) in the table below.

        Standard: 

        TESTER SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        LPL (2A-2) - Battery negative terminal Below 1 V
      3. Connect the battery negative lead to terminal HRLY of the J/B No.2.
        SYMBOL CONNECTION CHART

        Symbols (terminals No.) Connection
        HRLY (2H-8) Negative
      4. Measure the voltage according to the value (s) in the table below.

        Standard: 

        TESTER SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        LPL (2A-2) - Battery negative terminal 10 to 14 V
    1. NG: REPLACE JUNCTION BLOCK NO.2 
    2. OK: Go to next step. 
  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSY (HRLY SIGNAL CIRCUIT) 
    1. Disconnect the connector from the instrument panel J/B.

      HINT:

      Reconnect the J/B No.2 connector.

    2. Measure the voltage according to the value (s) in the table below.

      Standard: 

      TESTER SPECIFIED CONDITION CHART

      Tester connection Condition Specified value
      1D-3 - Body ground Always 10 to 14 V
      Fig 4: Instrument Panel Junction Block Assy Connector Location
      G03007443Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Go to step  8 . 
    2. OK: Go to next step. 
  6. CHECK HARNESS AND CONNECTOR (J/B NO.2 - BULB) (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    1. Disconnect the connectors from the J/B No.2 (power distributor) and headlight bulbs.
    2. Measure the resistance according to the value (s) in the table below.
      Fig 5: Disconnecting Connectors From J/B No.2 (Power Distributor)
      G03007444Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      TESTER SPECIFIED CONDITION CHART

      Tester connection Condition Specified value
      2A-2 (LPL) - H5-2 (Headlight LH) Always Below 1 Ω
      2A-3 (LPL) - H9-2 (Headlight RH) Always Below 1 Ω
      2A-2 (LPL) - body ground Always 10 kΩ or higher
      2A-3 (LPL) - body ground Always 10 kΩ or higher
      Fig 6: Identifying J\B No.2 Connector
      G03007445Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: Go to next step. 
  7. CHECK HARNESS AND CONNECTOR (BULB - BODY GROUND) (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    1. Measure the resistance according to the value (s) in the table below.

      Standard: 

      TESTER SPECIFIED CONDITION CHART

      Tester connection Condition Specified value
      H5-1 (Headlight LH) -Body ground Always Below 1 Ω
      H9-1 (Headlight RH) -Body ground Always Below 1 Ω
      Fig 7: Identifying Bulb - Body Ground Terminal Connector
      G03007446Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
  8. CHECK HARNESS AND CONNECTOR (J/B NO.2 - INSTRUMENT PANEL J/B) (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    1. Disconnect the connectors from the J/B No.2 (power distributor) and instrument panel J/B.
    2. Measure the resistance according to the value (s) in the table below.

      Standard: 

      TESTER SPECIFIED CONDITION CHART

      Tester connection Condition Specified value
      2H-8 (HRLY) - 1D-3 Always Below 1 Ω
      2H-8 (HRLY) -Body ground Always 10 kΩ or higher
      Fig 8: Identifying J/B No.2 - Instrument Panel J/B Connector
      G03007447Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 9: Locating J/B No.2 - Instrument Panel J/B Connector
      G03007448Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OF? REPLACE HARNESS OR CONNECTOR 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  
  9. CHECK HARNESS AND CONNECTOR (SHORT CIRCUIT DRIVEN SIDE BY RELAY) (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    1. Preparation
      1. For easier disconnection remove the J/B No.2 and then take apart the connectors.
      2. Disconnect only the connector "2A".
    2. Check voltage
      1. Measure the voltage between the Mode Monitor Terminal and body ground.

        Result: 

        VOLTAGE REFERENCE CHART

        6.3 +/- 2 V A
        Approx. 1 V B
        Fig 10: Checking Harness And Connector (Short Circuit Driven Side By Relay)
        G03007449Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: REPLACE JUNCTION BLOCK NO.2 
    2. A: REPAIR OR REPLACE HARNESS OR CONNECTOR (SHORT CIRCUIT BETWEEN HEADLIGHT LO AND J/B NO.2) 
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