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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) 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 engine switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG) and the Techstream on.
    4. Enter the following menus: Chassis / Air suspension / Data List.
    5. Check the values by referring to the table below.

    Air suspension 

    DIAGNOSTIC NOTE TABLE

    Tester Display Measurement Item/Range Normal Condition Diagnostic Note
    IG Power source Voltage ECU power supply voltage/
    min.: 0 V
    max.: 255 V    		 Engine switch on (IG): 11 to 14 V -

    OK: 11 to 14 V 

    Result 

    RESULT TABLE

    Result Proceed to
    NG A
    OK B

    B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

    A: Go to Next Step 

  2. INSPECT FUSE (AIRSUS) 
    1. Remove the AIRSUS fuse from the passenger side junction block.
    2. Measure the resistance of the fuse.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

    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 TABLE

    Tester Connection Switch Condition Specified Condition
    L88-1 (B) - L88-4 (GND) Engine switch on (IG) 11 to 14 V

    Result 

    RESULT TABLE

    Result Proceed to
    NG A
    OK B

    B: REPLACE SUSPENSION CONTROL ECU  (See REMOVAL  )

    A: Go to Next Step 

  4. CHECK HARNESS AND CONNECTOR (PASSENGER SIDE JUNCTION BLOCK - ECU AND BODY GROUND) 
    1. Disconnect the L88 ECU connector.
      2. Fig 1: Identifying L88 ECU Connector
      G04944173Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the PA passenger side junction block connector.
    3. Measure the resistance according to the value in the table below.
      4. Fig 2: Checking Harness & Connector (Passenger Side Junction Block - ECU & Body Ground)
      G04944174Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

    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 (BATTERY - PASSENGER SIDE JUNCTION BLOCK) 
    1. Disconnect the PL junction block connector.
    2. Measure the voltage according to the value(s) in the table below.

    Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

    Tester Connection Condition Specified Condition
    PL-1 - Body ground Always 11 to 14 V
    Fig 3: Identifying PL Junction Block Connector
    G04944175Courtesy 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 - JUNCTION BLOCK AND BODY GROUND) 
    1. Disconnect the PA junction block connector.
    2. Measure the voltage and resistance according to the value (s) in the table below.
      3. Fig 4: Identifying PA Junction Block Connector
      G04944176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

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

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

    Tester Connection Condition Specified Condition
    PA-39 - Body ground Always Below 1 Ω

    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 in the table below.
      4. Fig 5: Identifying L88 ECU Connector
      G05848072Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION TABLE

    Tester Connection Condition Specified Condition
    L88-1 (B) - Body ground Always 10 kΩ or higher

    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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