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Inspection Procedure

  1. INSPECT FRONT HEIGHT CONTROL SENSOR LH 
    1. Connect the 3 dry cell batteries (1.5 V) in series.
    2. Remove the front height control sensor LH.
    3. Connect the positive (+) lead from the battery to terminal 3 (SHB) and the negative (-) lead to terminal 1 (SHG).
    4. Measure the voltage between terminals 2 (SHFL) and 1 (SHG) while slowly moving the link up and down.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      2 (SHFL) -1 (SHG) +45° (High) Approx 4.5 V
      2 (SHFL) -1 (SHG) 0° (Normal) Approx 2.5 V
      2 (SHFL) -1 (SHG) -45° (Low) Approx 0.5 V
      Fig 1: Measuring Voltage Between Terminals 2 And 1
      G05298910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT HEIGHT CONTROL SENSOR LH 

    OK: GO TO Next Step 

  2. INSPECT REAR HEIGHT CONTROL SENSOR LH 
    1. Connect the 3 dry cell batteries (1.5 V) in series.
    2. Remove the rear height control sensor LH.
    3. Connect the positive (+) lead from the battery to terminal 3 (SHB) and the negative (-) lead to terminal 1 (SHG).
    4. Measure the voltage between terminals 2 (SHRL) and 1 (SHG) while slowly moving the link up and down.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      2 (SHRL) -1 (SHG) +45° (High) Approx 4.5 V
      2 (SHRL) - 1 (SHG) 0° (Normal) Approx 2.5 V
      2 (SHRL) -1 (SHG) -45° (Low) Approx 0.5 V
      Fig 2: Measuring Voltage Between Terminals 2 (SHRL) And 1 (SHG)
      G05298911Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE REAR HEIGHT CONTROL SENSOR LH 

    OK: GO TO Next Step 

  3. CHECK WIRE HARNESS (ECU - SENSOR) 
    1. Check the wire harness between the AFS ECU and front height control sensor LH.
      1. Disconnect the A28 ECU connector.
      2. Disconnect the A21 sensor connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        A28-17 (SGF) - A21-1 (SHG) Below 1 Ω
        A28-2 (SHFL) - A21-2 (SHFL) Below 1 Ω
        A28-1 (SBF) - A21-3 (SHB) Below 1 Ω
        A28-17 (SGF) or A21-1 (SHG) - Body ground 10 kΩ or higher
        A28-2 (SHFL) or A21-2 (SHFL) - Body ground 10 kΩ or higher
        A28-1 (SBF) or A21-3 (SHB) - Body ground 10 kΩ or higher
        Fig 3: Identifying A21 Front Height Control Sensor LH And A28 AFS ECU Connector Terminals
        G05315667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the wire harness between the AFS ECU and rear height control sensor LH.
      1. Disconnect the A29 ECU connector.
      2. Disconnect the o2 sensor connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        A29-20 (SGR) - o2-1 (SHG) Below 1 Ω
        A29-9 (SHRL) - o2-2 (SHRL) Below 1 Ω
        A29-10 (SBR) - o2-3 (SHB) Below 1 Ω
        A29-20 (SGR) or o2-1 (SHG) - Body ground 10 kΩ or higher
        A29-9 (SHRL) or o2-2 (SHRL) - Body ground 10 kΩ or higher
        A29-10 (SBR) or o2-3 (SHB) - Body ground 10 kΩ or higher
        Fig 4: Identifying A29 ECU And O2 Sensor Connector Terminals
        G05315668Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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