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Precaution [12/2019 - 10/2022]

WARNING: This page is about a different variant/trim than selected.
  1. PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL 
    NOTE:

    When disconnecting the cable from the negative (-) battery terminal, initialize the following system(s) after the cable is reconnected:

    System See Procedure
    Stop and Start System Refer to INITIALIZATION [12/2019 - 09/2020] , or refer to INITIALIZATION [09/2020 - 10/2021] , or refer to INITIALIZATION [10/2021 - 10/2022]
    Lane Control System
    Parking Support Brake System
    Pre-collision System
    Lighting System (EXT) (w/ AFS)
    Parking Assist Monitor System
    Panoramic View Monitor System
    Power Door Lock Control System
    Power Back Door System
  2. TROUBLESHOOTING PRECAUTION 
    NOTE:
    • Since the Dynamic Torque Control AWD system may be influenced by a malfunction in other systems, be sure to check for DTCs in the other systems.
    • After performing repairs, clear the DTCs and check that the DTCs are not output again.

      Refer to DTC CHECK / CLEAR [12/2019 - ] 

    • When replacing the 4WD ECU assembly, always replace it with a new one.
    • When the 4WD ECU assembly is replaced, before removing the 4WD ECU assembly, it is necessary to perform ECU Data Save to save the original 4WD ECU assembly information.

      Refer to CALIBRATION [12/2019 - ] 

    • When the 4WD ECU assembly is replaced, it is necessary to perform ECU Data Write.

      Refer to CALIBRATION [12/2019 - ] 

    • When the front 4WD linear solenoid (transfer assembly) or rear 4WD linear solenoid (rear differential carrier assembly) is replaced, it is necessary to perform the following in order: ECU Data Initialization and Disconnect System Function Check.

      Refer to CALIBRATION [12/2019 - ] 

    • When the temperature sensor is replaced, it is necessary to perform ECU Data Initialization.

      Refer to CALIBRATION [12/2019 - ] 

  3. PRECAUTIONS WHEN INSPECTING VEHICLE EQUIPPED WITH DYNAMIC TORQUE CONTROL AWD SYSTEM 
    1. When using speedometer tester
      NOTE:
      • Testers with a load setting mechanism for 2 wheels only (2-wheel chassis dynamometer, or any combination testers such as 2-wheel chassis dynamometer with speedometer tester or brake tester) cannot be used by themselves.
      • Perform the inspection on the front wheels.
      • Do not start off, accelerate or decelerate suddenly.
      • The vehicle speed should be 60 km/h (37 mph) or less (When a free roller is in use, the vehicle speed should be 50 km/h (31 mph) or less).
      • The driving time should be within 1 minute.
      1. Enter "AWD Control Prevention Mode".

        HINT: 

        Refer to "AWD Control Prevention Mode" Procedures for Inspection and Maintenance.

      2. Drive the vehicle and check that no AWD control operation status display graduations are displayed on the multi-information display for any wheel.
      3. Place the front wheels onto the roller.
      4. Place the rear wheels onto the free roller or safety stand.
        GTY854086Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *1 Safety Stand *2 Free Roller
        *a When using drum tester *b AWD control operation prohibited condition
      5. Secure the vehicle with lock chains.

        HINT: 

        The position of the lock chain in the illustration is for reference only.

      6. With the shift position in D, measure the vehicle speed while increasing the speed gradually.
      7. Slowly decelerate by the brake and stop the vehicle after the measurement.
        NOTE:

        Do not use the parking brake. If brake is applied only on the rear wheels during high engine speed, it may cause AWD function effectiveness to decline, drivetrain parts to malfunction or the vehicle to move unexpectedly.

      8. Cancel "AWD Control Prevention Mode".

        HINT: 

        Refer to "AWD Control Prevention Mode" Procedures for Inspection and Maintenance.

      9. With the AWD operation status display shown on the multi-information display, drive the vehicle and check that 1 or more graduations are displayed for any wheel when accelerating.
    2. When using brake tester
      NOTE:
      • A tester with a load measurement mechanism cannot be used.
      • A high-speed type brake tester cannot be used.
      1. Enter "AWD Control Prevention Mode".

        HINT: 

        Refer to "AWD Control Prevention Mode" Procedures for Inspection and Maintenance.

      2. Drive the vehicle and check that no AWD control operation status display graduations are displayed on the multi-information display for any wheel.
      3. Place the wheels to be tested (front or rear) onto the roller.
      4. Move the shift lever to N.
      5. Drive the roller of the brake tester and measure.

        HINT: 

        The driving time should be within 1 minute.

      6. Cancel "AWD Control Prevention Mode".

        HINT: 

        Refer to "AWD Control Prevention Mode" Procedures for Inspection and Maintenance.

      7. With the AWD operation status display shown on the multi-information display, drive the vehicle and check that 1 or more graduations are displayed for any wheel when accelerating.
    3. When using chassis dynamometer
      1. Check the following methods and set the vehicle in the appropriate condition.
      2. Drive the vehicle and check that no AWD control operation status display graduations are displayed on the multi-information display for any wheel.
      3. Use the following methods to perform the test.
        GTY498237Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *1 Propeller Shaft Assembly - -
        *a 2-wheel Chassis Dynamometer *b 4-wheel Driven Chassis Dynamometer
        (Mechanical Front/Back Synchronized Type)
        *c 4-wheel Driven Chassis Dynamometer
        (Electric Front/Back Synchronized Type)        		 - -
        Remove - -
        NOTE:
        • Do not suddenly accelerate or apply the brake.
        • Failure to observe the following methods may cause AWD function effectiveness to decline, drivetrain parts to malfunction or the vehicle to move unexpectedly.
          Vehicle Condition Chassis Dynamometer Vehicle Speed, Test Time Propeller Shaft Assembly 4WD ECU Assembly Connector
          *a
          (*1)          		 2-wheel Chassis Dynamometer No limit Remove Disconnected
          *b 4-wheel Driven Chassis Dynamometer
          (Mechanical Front/Back Synchronized Type)          		 No limit Normal Connected
          *c
          (*1) (*2)          		 4-wheel Driven Chassis Dynamometer
          (Electric Front/Back Synchronized Type)          		 No limit Remove Disconnected
          NOTE:
          • (*1): Disconnect the propeller shaft assembly and 4WD ECU assembly connector and perform the test in front wheel drive. If performed under other conditions, the "AWD System Overheated 2WD Mode Engaged" message is displayed on the multi-information display and the drivetrain may be damaged.
          • (*2): Do not use the electric front/back synchronized type 4-wheel driven chassis dynamometer with the propeller shaft assembly installed since the drivetrain may be damaged (However, use with the propeller shaft assembly removed is possible).
      4. Connect the propeller shaft assembly and 4WD ECU assembly connector and set the system to the AWD control operation permitted condition.
        NOTE:

        After measuring, make sure to connect the propeller shaft assembly and 4WD ECU assembly connector.

      5. With the AWD operation status display shown on the multi-information display, drive the vehicle and check that 1 or more graduations are displayed for any wheel when accelerating.
  4. CAUTIONS FOR TOWING DYNAMIC TORQUE CONTROL AWD VEHICLE 
    1. Tow the vehicle with all 4 wheels on the ground or lifted up. When towing the vehicle with all 4 wheels on the ground, limit the tow speed to 30 km/h (19 mph) or less and the tow distance to 80 km (50 miles) or less, and tow the vehicle in the forward direction.
      NOTE:

      If the vehicle is towed above this speed and beyond this distance or is towed in reverse direction, the transaxle may be affected or damaged.

    2. Do not tow with only the front or rear wheels lifted up. If the driving system or drivetrain is malfunctioning, transport the vehicle with all 4 wheels lifted up.
      GTY921102Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A Tow Truck (Rear Wheels on the Ground) *B Tow Truck (Front Wheels on the Ground)
      *C Tow Truck (Sling-type) - -
      NOTE:
      • Do not use a sling-type towing method. If a sling-type tow truck is used, damage may occur to the vehicle body.
      • Towing with only the front wheels or rear wheels lifted up may damage drivetrain parts or cause the wheels to jump out of the tow truck.
    3. Use one of the methods shown below to tow the vehicle.
      GTY935639Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A Car Carrier *B Tow Truck (4 Wheels Lifted)
      *C Tow Truck (4 Wheels on the Ground)
      - Limit the tow speed to 30 km/h (19 mph) or less
      - Limit the tow distance to 80 km (50 miles) or less      		 - -
      NOTE:
      • If there is a malfunction in the chassis or drivetrain, use the car carrier.
      • When towing the vehicle, do not use any towing method other than those shown in the illustration.
      PARKING BRAKE AND SHIFT LEVER DURING TOWING

      Towing Method Parking Brake Transmission Shift Lever Position
      Car Carrier Parking brake applied* Any position
      Tow Truck (4 Wheels Lifted) Parking brake applied* Any position
      Tow Truck (4 Wheels on the Ground) Parking brake not applied Shift position in N
      WARNING:

      *: The braking force of the electric parking brake changes according to the tilt of the vehicle. When towing the vehicle, pull the parking brake switch 2 times (2 lock operations) to apply the maximum amount of braking force to prevent the wheels from moving unexpectedly.

      HINT: 

      The steering lock cannot be released with the battery fully depleted or the cable disconnected from the negative (-) battery terminal.

  5. "AWD CONTROL PREVENTION MODE" PROCEDURES FOR INSPECTION AND MAINTENANCE 
    NOTE:

    In the case of using a speedometer tester, brake tester, or chassis dynamometer, etc., there is some possibility of a speed differential between the front and rear wheels. Therefore, before performing the test, make sure to enter "AWD Control Prevention Mode".

    1. When entering "AWD Control Prevention Mode" by disconnecting the 4WD ECU assembly connector:
      1. Enter "AWD Control Prevention Mode":
        1. Disconnect the 4WD ECU assembly connector.

          Refer to REMOVAL [12/2019 - ]

      2. Cancel "AWD Control Prevention Mode":
        1. Connect the 4WD ECU assembly connector.

          Refer to INSTALLATION [12/2019 - ]

          NOTE:

          After inspection, make sure to connect the 4WD ECU assembly connector.

    2. When entering "AWD Control Prevention Mode" manually:
      WARNING:

      When performing an inspection which requires removal of the propeller shaft, do not enter "AWD Control Prevention Mode" manually.

      1. Enter "AWD Control Prevention Mode":

        HINT: 

        • "AWD Control Prevention Mode" is canceled when the ignition switch is turned off. When continuing the inspection after the ignition switch has been turned off during inspection, re-enter "AWD Control Prevention Mode".
        • Do not drive the vehicle while in "AWD Control Prevention Mode".
        • Perform the operation within 30 seconds of starting the engine.
        • If it cannot be confirmed that "AWD Control Prevention Mode" has been entered, carry out the procedure again from step 1 after turning the ignition switch off.
        • Fully depress or release the brake pedal to ensure that the stop light switch changes between ON and OFF respectively.
        • Fully apply or release the parking brake to ensure that the parking brake light in the combination meter assembly illuminates or turns off respectively.
        1. Turn the ignition switch to ON.
        2. Observe Data List item "2WD Chassis Dynamometer Mode".
        3. With the parking brake applied, release and then depress the brake pedal 2 or more times consecutively, and then keep the brake pedal depressed.
        4. With the brake pedal depressed, release and then apply the parking brake 2 or more times consecutively, and then keep the parking brake applied.
        5. With the parking brake applied, release and then depress the brake pedal 2 or more times consecutively again.
        6. Confirm that the value of Data List item "2WD Chassis Dynamometer Mode" is "ON".

        Chassis > Four Wheel Drive > Data List 

        Tester Display
        2WD Chassis Dynamometer Mode

        Chassis > Four Wheel Drive > Data List 

        Tester Display Measurement Item Range Normal Condition Diagnostic Note
        2WD Chassis Dynamometer Mode 2WD chassis dynamometer mode Normal / ON - -
      2. Cancel "AWD Control Prevention Mode":
        1. Turn the ignition switch off, wait for 60 seconds or more, and cancel "AWD Control Prevention Mode".
          NOTE:

          Do not turn the ignition switch off within 60 seconds of entering "AWD Control Prevention Mode". If the ignition switch is turned off within 60 seconds, "AWD Control Prevention Mode" will continue when the ignition switch is turned to ON again.

        2. Confirm that the value of Data List item "2WD Chassis Dynamometer Mode" is "Normal".
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