LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2010 >> RX 350 FWD >> Repair and Diagnosis >> Accessories & Equipment >> Exterior Lights >> Lighting (Exterior) (Diagnostic Codes & Circuit Tests) >> Lighting System >> High Beam Headlight Circuit (From 08/2009) >> Procedure

High Beam Headlight Circuit (From 08/2009): Procedure

  1. CHECK OPERATION (LOW BEAM HEADLIGHTS) 
    1. Check the operation of the low beam headlights.

      OK

      Low beam headlights operate normally.

    NG → See step   10 

    OK: Go to next step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test.
    5. Check that the high beam headlights illuminate.
      MAIN BODY

      Tester Display Test Part Control Range
      Head Light Hi High beam headlights ON/OFF

      OK

      High beam headlights illuminate.

    NG → See step   3 

    OK → See step   8 

  3. CHECK HARNESS AND CONNECTOR (SHORT IN RELAY-DRIVEN CIRCUIT) 

    HINT: 

    When a short circuit occurs between the power distributor (engine room junction block assembly) and high beam headlight bulb, a fail-safe function operates to stop high beam headlight operation.

    1. Remove the H-LP RH HI fuse from the power distributor (engine room junction block assembly).
    2. Turn the light control switch to the head position and turn the dimmer switch to the high position.
    3. Check if the high beam headlight LH illuminates.
    4. Turn the dimmer switch to the low position.
    5. Install the H-LP RH HI fuse and remove the H-LP LH HI fuse.
    6. Turn the dimmer switch to the high position.
    7. Check if the high beam headlight RH illuminates.

      OK

      Either high beam headlight LH or RH illuminates.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. INSPECT POWER DISTRIBUTOR (ENGINE ROOM JUNCTION BLOCK ASSEMBLY) 
    1. Remove the power distributor (engine room junction block assembly) from the engine room relay block. Refer to COMPONENTS .
      Fig 1: Inspecting Power Distributor (Engine Room Junction Block Assembly)
      GTY286825Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect a positive (+) lead from the battery to terminal 3A-1.
    3. Connect a negative (-) lead from the battery to terminals 3C-5 and 3C-17.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      3B-1 - Battery negative Always 11 to 14 V
      3B-5 - Battery negative Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Power Distributor (Engine Room Junction Block Assembly))

    NG → See step   7 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (POWER DISTRIBUTOR - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the 3C power distributor (engine room junction block assembly) connector.
      Fig 2: Identifying 3C Power Distributor (Engine Room Junction Block Assembly) & 2F Instrument Panel Junction Block Assembly Connector
      GTY259667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the 2F instrument panel junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3C-5 - 2F-20 Always Below 1 Ω
      3C-5 - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Power Distributor (Engine Room Junction Block Assembly))
      *2 Front view of wire harness connector
      (to Instrument Panel Junction Block Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly.
      Fig 3: Inspecting Instrument Panel Junction Block Assembly
      GTY281385Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2F-20 - A-22 (DIM) Always Below 1 Ω
      2F-20 - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    OK → See step   9 

  7. REPLACE POWER DISTRIBUTOR (ENGINE ROOM JUNCTION BLOCK ASSEMBLY). Refer to  COMPONENTS 
  8. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE 
  9. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  COMPONENTS 
  10. GO TO PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE