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Inspection Procedure

WARNING: This page is about a different car, the 2004 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK LIGHT 
    1. Check that tail light and head light light up.
    1. NG: FLOW CHART (GO TO FLOW CHART OF HEAD LIGHT OR TAIL LIGHT) 
    2. OK: Go to next step. 
  2. INSPECT HEADLAMP DIMMER SWITCH ASSY (AUTO) 
    1. Inspect light control switch continuity.
      1. Check that there is continuity between terminals at each switch position as shown in the chart.
      SPECIFIED CONDITION

      Switch operation Tester connection Specified condition
      OFF - No continuity
      AUTO 12 - 16 Continuity
      Fig 1: Inspecting Headlamp Dimmer Switch Assembly (Auto)
      G02894858Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE HEADLAMP DIMMER SWITCH ASSY 
    2. OK: Go to next step. 
  3. CHECK AUTOMATIC LIGHT CONTROL SENSOR 
    1. Check the continuity between terminal 3 (+) and body ground as shown in the chart below.
    2. Measure voltage between terminals as shown in the chart below.
    3. Using an oscilloscope, check that signal waveform appears between terminals.
      Fig 2: Identifying Automatic Light Control Sensor
      G02894859Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      SPECIFIED CONDITION

      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
    1. OK: FLOW CHART (GO TO FLOW CHART OF HEAD LIGHT OR TAIL LIGHT) 
    2. NG: Go to next step. 
  4. CHECK HARNESS AND CONNECTOR (BETWEEN INSTRUMENT PANEL J/B ASSY AND AUTOMATIC LIGHT CONTROL SENSOR) 
    1. Check that signal waveform appears between terminal B7 - 17 (CLTS) and body ground.

      Standard: Bar appears. 

    1. OK: CHECK AND REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY 
    2. NG: Go to next step. 
  5. CHECK HARNESS AND CONNECTOR (BETWEEN INSTRUMENT PANEL J/B ASSY AND AUTOMATIC LIGHT CONTROL SENSOR) 
    1. Measure voltage between terminal B7 - 15 (CLTB) and body ground.

      Standard: 10 - 14 V 

    1. OK: CHECK AND REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY 
    2. NG: Go to next step. 
  6. CHECK HARNESS AND CONNECTOR (BETWEEN INSTRUMENT PANEL J/B ASSY AND AUTOMATIC LIGHT CONTROL SENSOR) 
    1. Check the continuity between terminal B7 - 16 (CLTE) of instrument panel J/B and 3 (CLTE) of automatic light control sensor.

      Standard: There is continuity. 

    1. OK: CHECK AND REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSY 
    2. NG: REPLACE AUTOMATIC LIGHT CONTROL SENSOR 
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