LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2007 >> RX 400h AWD >> Repair and Diagnosis >> Accessories & Equipment >> Headlights >> Lighting >> Lighting System >> DRL Relay Circuit >> Inspection Procedure
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Inspection Procedure

  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER 
    1. Connect the intelligent tester to DLC3.
    2. Turn the ignition switch ON and push the intelligent tester main switch ON.
    3. Select the item below in the ACTIVE TEST and then check that the relay operates.

    BODY 

    BODY ITEM REFERENCE CHART

    Item Test Details Diagnostic Note
    HEAD LIGHT (HI) Turn DRL No.2, DRL No. 3 and DRL No.4 relays ON/OFF -
    DRL Turn DRL No.2 relay ON/OFF -

    OK: High beam headlights come on. Daytime running lights (Dimmed high beam headlights) come on. 

    NG: GO TO step   2 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  2. INSPECT DAY TIME RUNNING LIGHT RELAY NO.3 (DRL NO. 3 RELAY) 
    1. Inspect DRL No.3 relay continuity.
      1. Remove the relay from the relay block No. 3.
      2. Check the resistance between the each of the terminals as shown in the table below.

    Resistance 

    TESTER SPECIFIED CONDITION REFERENCE CHART

    Terminal No. Specified condition
    3 - 5 10 kΩ or higher
    Below 1 Ω (When battery voltage is applied to terminals 1 and 2)
    3 - 4 Below 1 Ω
    10 kΩ or higher (When battery voltage is applied to terminals 1 and 2)

    NG: REPLACE DAY TIME RUNNING LIGHT RELAY NO.3 

    Fig 1: Inspecting Day Time Running Light Relay No.3 (DRL NO. 3 Relay)
    G05204214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) 
    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.

    Voltage 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    2I -1 (+B) - Body ground Always 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Disconnecting Connector From J/B No.2 (Power Distributor)
    G05273782Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  4. CHECK MODE MONITOR TERMINAL (DRL NO. 2, DRL NO. 4 RELAY) 
    1. Preparation
      1. Connect the connector.
      2. Remove the cover of the fusible link block assembly.
      3. Set the vehicle to the following condition.
        • Ignition switch ON.
        • Headlight dimmer switch HI (FLASH).
    2. Check voltage
      1. Measure the voltage between the Mode Monitor Terminal and body ground.

    Voltage 

    RESULT CHART

    Result Proceed to
    0 V or Approx. 12 V A
    Approx. 6.2 V B
    Approx. 2.0 V C

    B: GO TO step   6 

    C: GO TO step   12 

    Fig 3: Checking Mode Monitor Terminal (DRL NO. 2, DRL NO. 4 Relay)
    G05201886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (J/B NO. 2 - MODE MONITOR TERMINAL) 
    1. Disconnect the 2G connector from the J/B No.2.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    2G-5 - Mode monitor terminal Always Below 1 Ω
    26-5 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying J/B No.2 And Fusible Link Block Connector Terminal
    G05280033Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  6. INSPECT JUNCTION BLOCK NO.2 (DRL NO. 2, DRL NO. 4 RELAY) 
    1. Turn the ignition switch to OFF position.
    2. Remove the J/B No.2.
    3. Inspect the DRL No.2 relay.
      Fig 5: Inspecting Junction Block No. 2 (DRL NO. 2, DRL NO. 4 Relay)
      G05280044Courtesy 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 REFERENCE 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.

        Voltage 

        TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

        Tester Connection Specified Condition
        DRL2 (2I-2) - Battery negative terminal Below 1 V
      3. Connect the battery negative lead to terminal DRL of the J/B No.2.
        SYMBOL CONNECTION REFERENCE CHART

        Symbols (terminals No.) Connection
        DRL (2H-7) Negative
      4. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      DRL2 (2I-2) - Battery negative terminal 10 to 14 V
    4. Inspect the DRL No.4 relay.
    1. Connect terminal HRE and DRL with wire.
      SYMBOL CONNECTION REFERENCE CHART

      Symbols (terminals No.) Connection
      HRE (2G-10) - DRL (2H-7) Using wire harness
    2. Connect the positive battery lead to terminal +B of the J/B No.2 and the negative lead to terminal SGND, PGND.
      SYMBOL CONNECTION REFERENCE CHART

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

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      DRL2 (2I-2) - Battery negative terminal Below 1 V
    4. Connect the battery negative lead to terminal HRLY of the J/B No.2.
      SYMBOL CONNECTION REFERENCE CHART

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

    Voltage 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Specified Condition
    DRL2 (2I-2) - Battery negative terminal 10 to 14 V

    NG: REPLACE JUNCTION BLOCK NO.2 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (J/B NO. 2 - INSTRUMENT PANEL J/B) 
    1. Disconnect the connectors from the instrument panel J/ B.
      Fig 6: Identifying J/B No. 2 And Instrument Panel J/B Connector Terminals
      G05280045Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    2H-7 (DRL) - 1D-9 Always Below 1 Ω
    2H-7 (DRL) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (J/B NO. 2 - BULB) 
    1. Disconnect the connectors from the J/B No.2 (power distributor) and headlight bulb.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    21-2 (DRL2) - H4-2 (Headlight LH) Always Below 1 Ω
    21-2 (DRL2) - body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 7: Identifying J/B No. 2 And Headlight Bulb Connector Terminals
    G05280046Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (BULB - J/B NO. 2) 
    1. Disconnect the connectors from the J/B No.2 (power distributor).
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    2G-11 (HLE) - H4-1 (Headlight LH) Always Below 1 Ω
    2G-11 (HLE) - Body ground Always 10 kΩ or higher
    2G-10 (HRE) - H8-1 (Headlight RH) Always Below 1 Ω
    2G-10 (HRE) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 8: Disconnecting Connectors From J/B No.2 (Power Distributor)
    G05280047Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (BULB - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    H8-2 (Headlight RH) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 9: Identifying Bulb Connector Terminals
    G05280048Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (J/B NO. 2 - RELAY BLOCK NO. 3) 
    1. Remove the DRL No.3 relay from the relay block No.3.
    2. Measure the resistance according to the value(s) in the table below.

    Resistance 

    TESTER CONNECTION SPECIFIED VALUE REFERENCE CHART

    Tester connection Condition Specified value
    2I-2 (DRL2) - 5 (Relay block No.3) Always Below 1 Ω
    21-2 (DRL2) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 10: Identifying J/B NO. 2 DRL And Relay Block NO. 3 DRL NO. 3 Relay
    G05280049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  12. CHECK MODE MONITOR TERMINAL (SHORT CIRCUIT DRIVEN SIDE BY RELAY) 
    1. Disconnect the 2I connector from the J/B No.2.
    2. Connect the battery positive lead to terminal 2I-1 on the J/B side and negative lead to the body ground.
    3. Check voltage
      1. Measure the voltage between the Mode Monitor Terminal and body ground.

    Voltage 

    RESULT CHART

    Result Proceed to
    Approx. 6.2 V A
    Approx. 2 V B

    B: REPLACE JUNCTION BLOCK NO.2 

    Fig 11: Identifying Mode Monitor Terminal
    G05280050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: REPAIR OR REPLACE HARNESS OR CONNECTOR (SHORT CIRCUIT DRIVEN SIDE BY RELAY) 

scientia non olet · About LEMON Manuals