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Inspection Procedure

NOTE:
  • Before performing troubleshooting, inspect the connectors of related circuits.
  • Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation (see ELECTRONIC CIRCUIT INSPECTION PROCEDURE ); 2) DTC inspection; and 3) Intelligent tester or Techstream inspection (Data List or Active Test). If no malfunctions are found in other areas, replace the suspension control ECU.
  • If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed (see INITIALIZATION  ).
  1. CHECK IG VOLTAGE (DATA LIST) 
    1. Turn the power switch OFF.
    2. Connect the Intelligent tester or Techstream to the DLC3
    3. Turn the power switch ON (IG) and the tester ON.
    4. Enter the following menus.
      1. Intelligent tester - Select. DIAGNOSIS / OBD/MOBD / CHASSIS / AIR SUSPENSION / DATA LIST
      2. Techstream - Select: Chassis / Air suspension / Data List
    5. Check the values by referring to the table below.
      1. Intelligent tester

        AIR SUSPENSION 

        DIAGNOSIS NOTE NORMAL CONDITION CHART

        Tester Display Measurement Item/Range Normal Condition
        IG VOLTAGE ECU power supply voltage /
        min: 0 V
        max: 255 V        		 Power switch is ON (IG) 11 to 14 V
      2. Techstream

        Air suspension 

        DIAGNOSIS NOTE NORMAL CONDITION CHART

        Tester Display Measurement Item/Range Normal Condition
        IG Power source Voltage ECU power supply voltage /
        min: 0V
        max: 255 V        		 Power switch is ON (IG) 11 to 14 V

        OK: 11 to 14 V 

    NG: Go to step 2 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See TERMINALS OF ECU  )

  2. INSPECT FUSE (AIRSUS) 
    1. Remove the AIRSUS fuse from the passenger side junction block
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      AIRSUS fuse Always Below 1 Ω

    NG:  Go to step  7

    OK: Go to next Step 

  3. INSPECT PASSENGER SIDE JUNCTION BLOCK (AIRSUS RELAY) 
    1. Disconnect the L88 ECU connector
    2. Measure the voltage according to the value (s) in the table below

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      L88-1 (B) - L.88-4 (GND) Power switch ON (IG) 11 to 14 V
    Fig 1: Identifying ECU Connector L88
    G05773751Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 4 

    OK: REPLACE SUSPENSION CONTROL ECU  (See REMOVAL  )

  4. CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK - ECU AND BODY GROUND) 
    1. Disconnect the L88 ECU connector
    2. Disconnect the PA passenger side junction block connector.
    3. Measure the resistance according to the value (s) in the table below
      Fig 2: Identifying L88 ECU Connector And Passenger Side Junction Block Connector Terminal PA
      G05773757Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      L88-1 (B) - PA-44 Always Below 1 Ω
      L88-4 (GND) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  5. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - PASSENGER SIDE JUNCTION BLOCK) 
    1. Disconnect the PL passenger side junction block connector.
    2. Measure the voltage according to the value (s) in the table below

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      PL-1 - Body ground Always 11 to 14 V
    Fig 3: Identifying PL Passenger Side Junction Block Connector Terminal
    G05773758Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - PASSENGER SIDE JUNCTION BLOCK AND BODY GROUND) 
    1. Disconnect the PA passenger side junction block connector
    2. Measure the voltage and resistance according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      PA-15 - Body ground Power switch ON (IG) 11 to 14 V

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      PA-39 - Body ground Always Below 1 Ω
    Fig 4: Identifying PA Passenger Side Junction Block Connector Terminal
    G04944176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  7. CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK - ECU) 
    1. Disconnect the L88 ECU connector
    2. Connect the PA passenger side junction block connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      L88-1 (B) - Body ground Always 10 kΩ or higher
      Fig 5: Identifying ECU Connector L88
      G05773751Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      If the fuse is blown, replace the fuse.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE PASSENGER SIDE JUNCTION BLOCK 

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