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Headlight Beam Level Control ECU Communication Circuit: Wiring Diagram

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Wiring Diagram - Headlight Beam Level Control ECU Communication Circuit
G04115032Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B - HEADLIGHT BEAM LEVEL CONTROL ECU) 
    1. Disconnect the 1D connector of instrument panel junction block assembly and the H17 connector of headlight beam level control ECU.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 2: Identifying Headlight Beam Level Control ECU Connector Terminals
      G04115033Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 3: Identifying Instrument Panel Junction Block Assembly Connector Terminals (Front Side)
      G04115034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION - SPECIFIED CONDITION (RESISTANCE)

      Tester connection Condition Specified condition
      1D-3 - H17-7 Always Below 1 Ω

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK : GO TO NEXT STEP 

  2. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - HEADLIGHT BEAM LEVEL CONTROL ECU) 
    1. Disconnect the connectors from the skid control ECU and the headlight beam level control ECU.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 4: Identifying Connectors From Skid Control ECU And Headlight Beam Level Control ECU
      G04115035Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION - SPECIFIED CONDITION (RESISTANCE)

      Tester connection Condition Specified condition
      S40-33 (RRO) - H17-6 (SPDR) Always Below 1 Ω
      S39-25 (RLO) - H17-5 (SPDL) Always Below 1 Ω

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

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