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Inspection Procedure

WARNING: This page is about a different car, the 2004 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK LIGHT 
    1. Check that headlamp and taillight light up.

    NG: FLOW CHART (GO TO FLOW CHART OF HEADLIGHT OR TAILLIGHT) 

    OK: Go To Next Step 

  2. INSPECT HEADLAMP DIMMER SWITCH ASSY 
    1. Inspect light control switch continuity.
      1. Check that there is a continuity between terminals at each switch position as shown in the chart.
      Fig 1: Inspecting Headlamp Dimmer Switch Assy
      G02834982Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    STANDARD

    Switch operation Tester connection Specified condition
    OFF - No continuity
    TAIL 14 - 16 Continuity
    HEAD 13 - 16 - 14 Continuity
    AUTO 16 - 12 Continuity

    NG: REPLACE HEADLAMP DIMMER SWITCH ASSY 

    OK: Go To Next Step 

  3. CHECK AUTOMATIC LIGHT CONTROL SENSOR 
    1. Measure voltage between terminals as shown in the chart below.
    2. Check the continuity between terminal 3 (CLTE) and body ground as shown in the table below.
      Fig 2: Locating Automatic Light Control Sensor Terminals
      G02834983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using an oscilloscope, check that signal waveform appears between terminals.
    STANDARD

    Terminal No. (Symbol) Tester connection Condition Specified condition
    1 (CLTB) 1 - 3 Constant 10 - 14 V
    3 (CLTE) 3 - Body ground Constant Continuity
    4 (CLTS) 4 - 3 IG SW ON Dimmer SW AUTO Signal waveform appears depending on outside brightness

    NG: REPLACE AUTOMATIC LIGHT CONTROL SENSOR 

    OK: Go To Next Step 

  4. CHECK HARNESS AND CONNECTOR (BETWEEN MULTIPLEX NETWORK BODY ECU AND AUTOMATIC LIGHT CONTROL SENSOR) 
    1. Check that signal waveform appears between terminal B6-4 (CLTS) and B6-21 (CLTE) of the multiplex network body ECU.

      Standard: Bar appears 

    2. Measure voltage between terminals B6-6 (CLTB) and B6-21 (CLTE) of the multiplex network body ECU.

      Standard: 10-14 V 

    3. Check the continuity between terminal B6-21 (CLTE) of the multiplex network body ECU and body ground.

    Standard: There is continuity 

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPLACE MULTIPLEX NETWORK BODY ECU