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Precaution [12/2017 - 10/2023]

  1. TROUBLESHOOTING PRECAUTIONS 
    1. If a problem is caused by a poor connection of a terminal or poor installation of a part, reconnecting the terminal or removing and reinstalling the part may solve the problem or may temporarily return the system to normal.
    2. To determine the cause of a problem, check for DTCs or confirm the vehicle operating conditions when the problem occurred and note them down before disconnecting connectors or removing parts.
    3. Be sure to check for DTCs in other systems as a problem may be caused by a malfunction in another system.
    4. Other systems may store DTCs when the VGRS system is inspected. Therefore, check and clear any DTCs from other systems after inspecting the VGRS system.
  2. HANDLING AND OPERATING PRECAUTIONS 
    1. Removal and installation of the VGRS ECU (front steering control ECU), steering actuator assembly and each sensor must be performed with the engine switch off unless specified.
    2. If the VGRS ECU (front steering control ECU), steering actuator assembly or a sensor is removed and installed, perform the test mode inspection, check for DTCs, and confirm that the normal system code is output.
    3. Other systems may store DTCs when the engine switch is turned on (IG) with the connector of the VGRS ECU (front steering control ECU) disconnected. Therefore, after performing repairs, check and clear DTCs for other systems.
  3. CONDITIONS UNDER WHICH VGRS SYSTEM DOES NOT OPERATE 
    1. The VGRS system does not operate under any of the following conditions:
      1. The power supply voltage is low or too high.
      2. A fail-safe function is operating to protect the system from overheating. System control is suspended to prevent the motor in the steering actuator assembly and the VGRS ECU (front steering control ECU) from overheating. If the temperatures of the motor and ECU drop, the system returns to normal.
      3. Steering sensor zero point calibration has not been performed.
  4. PRECAUTIONS FOR STEERING WHEEL OFF-CENTER 
    1. If parts between the steering wheel and tires have been removed/installed, replaced or adjusted, perform actuator angle neutral point calibration and initialization for the VGRS system, otherwise the steering wheel may become off-center.

      Refer to CALIBRATION [12/2017 - 10/2023] 

      Example: 

      • The VGRS ECU (front steering control ECU) has been replaced or removed/installed.
      • The steering actuator assembly has been replaced or removed/installed.
      • The steering wheel assembly has been replaced or removed/installed.
      • The steering column assembly has been replaced or removed/installed.
      • The steering sliding with shaft yoke sub-assembly has been separated.
      • The front wheel alignment has been adjusted.
      • The rack and pinion power steering gear assembly has been replaced or removed/installed.
    2. When steering angle sensor zero point calibration is not performed (battery cable or steering angle sensor system connector or fuse is disconnected), a steering wheel neutral position deviation may occur.

      Refer to INITIALIZATION [12/2017 - 10/2023] 

    3. When steering operations are rapidly performed while driving at low speeds, a steering wheel neutral position deviation may temporarily occur. Also, if the vehicle speed is increased while driving in a straight line when the steering angle sensor zero point is being calibrated, the steering wheel neutral position deviation is automatically corrected.
    4. If one of the situations under Conditions Under Which VGRS System does Not Operate occurs, the steering wheel may temporarily become off-centered.
  5. PRECAUTIONS WHEN PERFORMING STEERING OFF CENTER ADJUSTMENT 
    1. When adjusting the steering off center, make sure to adjust the front side wheel alignment after adjusting the rear side wheel alignment.
      1. Rear wheel alignment: Refer to ADJUSTMENT [12/2017 - 09/2018] , or refer to ADJUSTMENT [09/2018 - 10/2020] , or refer to ADJUSTMENT [10/2020 - 10/2022] , or refer to ADJUSTMENT [10/2022 - 10/2023]
      2. Front wheel alignment: Refer to ADJUSTMENT [12/2017 - 09/2018] , or refer to ADJUSTMENT [09/2018 - 10/2020] , or refer to ADJUSTMENT [10/2020 - 10/2023]
    2. When adjusting the steering wheel neutral position deviation, check the following before performing mechanical adjustments such as tie rod and steering wheel removal and installation.
      1. Check whether the steering zero point has been calibrated by checking the Data List "Direct Advance Wheel Angle Status".

        Refer to DATA LIST / ACTIVE TEST [12/2017 - 10/2023] 

      2. After slowly rotating the steering 360° left and right 2 or 3 times, check whether steering wheel neutral position deviation occurs while driving the vehicle at a speed of 40 km/h or higher as displayed on the meter.
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