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Inspection Procedure

  1. CHECK LIGHT CONTROL RHEOSTAT 
    1. Check that the illumination of the radio and player, center cluster module switch, etc. can be adjusted by the rheostat.

      OK : The illumination can be adjusted. 

      1. NG : Go to step   6 
      2. OK : GO TO NEXT STEP. 
  2. INSPECT COMBINATION METER ASSY 
    1. Disconnect the C10 connector.
    2. Measure the voltage between the terminal and body ground.

      Standard: 

      COMBINATION METER

      Tester Connection Condition Specified Condition
      C10-12 - Body ground Ignition switch is ON and lamp control switch is at TAIL or HEAD 10 to 14 V
      Fig 1: Inspecting Combination Meter Assembly
      G03196865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (COMBINATION SWITCH - COMBINATION METER ASSY) 
    2. OK : GO TO NEXT STEP. 
  3. CHECK HARNESS AND CONNECTOR (LIGHT CONTROL RHEOSTAT - COMBINATION METER ASSY) 
    1. Disconnect the C11 and R6 connectors.
    2. Measure the resistance between the terminals.

      Standard: 

      LIGHT CONTROL RHEOSTAT - COMBINATION METER

      Tester Connection Specified Condition
      C11-7 - R6-3 Below 1 Ω
      Fig 2: Checking Harness And Connector (Light Control Rheostat - Combination Meter)
      G03196866Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK : GO TO NEXT STEP. 
  4. INSPECT LIGHT CONTROL RHEOSTAT 
    1. Disconnect the R6 connector.
    2. Measure the voltage between the terminal and body ground.

      Standard: 

      LIGHT CONTROL RHEOSTAT

      Tester Connection Condition Specified Condition
      R6-3 - Body ground Ignition switch is ON and lamp control switch is at TAIL or HEAD 10 to 14 V
      Fig 3: Inspecting Light Control Rheostat
      G03196867Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG : REPLACE COMBINATION METER ASSY (See  INSTRUMENT PANEL/METER  ) 
    2. OK : GO TO NEXT STEP. 
  5. INSPECT COMBINATION METER ASSY 
    1. Check input signal waveform.
      1. Remove the combination meter but do not disconnect the connectors.
      2. Connect the oscilloscope to terminal C11-7 and body ground.
      3. Turn the ignition switch ON.
        Fig 4: Connecting Oscilloscope To Terminal C11-7 & Body Ground
        G03196868Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Check the signal waveform according to COMBINATION METER ASSY  .
        COMBINATION METER ASSY

        Item Contents
        Tool setting 2V/DIV., 1 msec./DIV.
        Vehicle condition Ignition switch ON
        Fig 5: Checking Signal Waveform
        G03196869Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK : As shown in  Fig 5  . 

        HINT: Duty ratio changes as illumination dims ("A" becomes longer).

    1. NG : REPLACE LIGHT CONTROL RHEOSTAT 
    2. OK : REPLACE COMBINATION METER ASSY (See  INSTRUMENT PANEL/METER  ) 
  6. INSPECT LIGHT CONTROL RHEOSTAT 
    1. Measure the voltage and resistance between the terminal and body ground.

      Standard: 

      LIGHT CONTROL RHEOSTAT

      Tester Connection Condition Specified Condition
      R6-1 - Body ground Ignition switch is ON 10 to 14 V
      R6-4 - Body ground Ignition switch is ON and lamp control switch is at TAIL or HEAD 10 to 14 V
      R6-5 - Body ground Always Below 1 Ω
      Fig 6: Inspecting Light Control Rheostat
      G03196870Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK : REPLACE LIGHT CONTROL RHEOSTAT 
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