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Inspection Procedure

  1. REMOVE OPTIONAL PARTS(CELLULAR MOBILE TELEPHONE) 
    1. Remove optional parts (Cellular mobile telephone) 
      1. Disconnect the cellular mobile telephone wire harness.
      2. Connect the wire harness of the navigation system so that the cellular mobile telephone is not linked.
    2. Check that the malfunction disappear when operate the navigation system again.
      MALFUNCTION CHART

      A B
      Malfunction does not disappear or w/o cellular mobile telephone Malfunction disappear
    1. B: CHECK AND REPLACE TELEPHONE COMPUTER AND WIRE HARNESS 
    2. A: GO TO NEXT STEP. 
  2. INSPECT NAVIGATION ECU (+B, ACC, GND) 
    1. Remove the navigation ECU with connectors with still connected.
    2. Check voltage.
      1. Measure voltage between terminals +B, ACC and GND of navigation ECU at each conditions, as shown in the chart.

      Voltage: 

      TERMINAL SPECIFICATIONS

      Terminal Condition Voltage (v)
      + <=> GND Constant 10 - 14 V
      ACC <=> GND Turn ignition switch ACC 10 - 14 V
      Fig 1: Measuring Voltage Between Terminals +B, ACC & GND Of Navigation ECU
      G03386780Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check continuity.
      1. Check that the continuity exists between terminal GND of navigation ECU and body ground.

      Standard: Continuity exists 

    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: GO TO NEXT STEP. 
  3. INSPECT NAVIGATION ECU (SYNC, VR, VG) 
    1. Check signal waveform.
      1. Using an oscilloscope, check signal waveform between terminals SYNC and GND of navigation ECU
      OSCILLOSCOPE SPECIFICATIONS

      Item Contents
      Tool setting 500 mV/DIV, 10 MUEs/ DIV
      Condition Navigation display is displayed
      Fig 2: Inspecting Navigation ECU (SYNC, VR, VG)
      G03386781Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check continuity.
      1. Check that the continuity exists between each terminals, as shown in the chart.

      Standard: 

      TERMINAL SPECIFICATIONS

      Terminal Condition Specified condition
      VR <=> Body ground Constant Continuity
      VG <=> Body ground Constant Continuity
      Fig 3: Checking Signal Waveform
      G03386782Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: CHECK AND REPLACE NAVIGATION ECU 
    2. OK: GO TO NEXT STEP. 
  4. INSPECT MULTI-DISPLAY (CRT DISPLAY) DISPLAY(SYNC, VR, VG) 
    1. Check signal waveform.
      1. Using an oscilloscope, check signal waveform between terminals SYNC and GND of multi-display.
      OSCILLOSCOPE SPECIFICATIONS

      Item Contents
      Too setting 500 mV/ DIV, 10 MUEs/ DIV
      Condition Navigation display is displayed
      Fig 4: Checking Continuity Exists Between Terminals
      G03386783Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check continuity.
      1. Check that the continuity exists between each terminals, as shown in the chart.

      Standard: 

      TERMINAL SPECIFICATIONS

      Terminal Condition Specified condition
      VR <=> Body ground Constant Continuity
      VG <=> Body ground Constant Continuity
      Fig 5: Checking Signal Waveform
      G03386784Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: CHECK AND REPLACE MULTI-DISPLAY (CRT DISPLAY) DISPLAY 
    2. NG: GO TO NEXT STEP. 
  5. CHECK HARNESS AND CONNECTOR(BETWEEN INSTRUMENT CLUSTER FINISH PANEL SUB-ASSY CENTER AND NAVIGATION ECU) 
    1. NG: REPAIR OR REPLACE HARNESS OR, CONNECTOR 
    2. OK: GO TO NEXT STEP. 
  6. CHECK HARNESS AND CONNECTOR(BETWEEN INSTRUMENT CLUSTER FINISH PANEL SUB-ASSY AND MULTI-DISPLAY) 
    1. NG: CHECK AND REPLACE INSTRUMENT CLUSTER FINISH PANEL SUB-ASSY CENTER 
    2. OK: CHECK AND REPLACE MULTI-DISPLAY (CRT DISPLAY) DISPLAY 
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