Variable Gear Ratio Steering System Precaution

Steering. Lexus Gs430, Gs300. Uzs190 Grs190
Steering Column. Lexus Gs430, Gs300. Uzs190 Grs190

  1. TROUBLESHOOTING PRECAUTIONS

  1. HANDLING AND OPERATIONAL PRECAUTIONS

  1. PRECAUTIONS FOR REPLACEMENT OF STEERING SYSTEM PARTS

  1. PRECAUTIONS FOR STEERING WHEEL OFF-CENTER

  1. CONDITIONS UNDER WHICH VGRS SYSTEM DOES NOT OPERATE

Variable Gear Ratio Steering System -- Precaution


CAUTION:
If the negative (-) battery cable has been disconnected, initialize the following systems when the cable is reconnected.

System
See procedure
Clearance Sonar System
Click here
Power Window Control System
Click here
Sliding Roof System
Click here
Variable Gear Ratio Steering System
Click here

1.TROUBLESHOOTING PRECAUTIONS

  1. If the 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 specify the cause of the problem, check for DTCs or confirm 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 the problem may be caused by a malfunction in another system.

  4. DTCs may be stored in the EPS and/or ECB systems due to VGRS system inspections. Check for DTCs in the EPS and ECB systems and clear any output codes after inspecting the VGRS system.

  5. When the engine switch is turned on/off, system start-up/stop operation is performed. At this time, a small operating sound can be heard and the steering wheel slightly moves in a turning direction.

  6. If "INVALID" is displayed for "STRAIGH ANG FLG" in the data list, the VGRS system does not operate.

  7. If the steering wheel is turned left and right with the engine switch off, a noise can be heard. However, this is not a malfunction.


2.HANDLING AND OPERATIONAL PRECAUTIONS

  1. Removal and installation of the steering control ECU, steering actuator, and each sensor must be performed with the engine switch off unless specified.

  2. If the steering control ECU, steering actuator, 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. If the engine switch is turned on (IG) with the steering control ECU connector disconnected, DTCs may be stored in the EPS and/or ECB systems. Check for DTCs in those systems and clear any output codes after completing repair.


3.PRECAUTIONS FOR REPLACEMENT OF STEERING SYSTEM PARTS

  1. If the steering control ECU or steering actuator is replaced, perform actuator angle neutral point calibration and initialization.

  2. The steering control ECU cannot be disassembled or repaired. If there is any problem with the steering control ECU, replace with a new one.


4.PRECAUTIONS FOR STEERING WHEEL OFF-CENTER
NOTICE:
If the steering wheel is still off-center after completing steering angle sensor initialization (Click here), perform VGRS system calibration (Click here).
HINT:
The steering wheel may become off-center under any of the following conditions.
These conditions do not indicate a malfunction.
  1. The steering wheel is turned when the engine switch is off.
  2. The steering wheel is turned quickly.
  3. The steering wheel is turned to the left or right lock position.
If the steering wheel is off-center, drive the vehicle at 35 km/h (22 mph) or more for 5 seconds or more, or turn the steering wheel to the left and right with the vehicle stopped or while driving at low speeds. This may center the steering wheel.

5.CONDITIONS UNDER WHICH VGRS SYSTEM DOES NOT OPERATE

  1. The VGRS system does not operate under any of the following conditions:

    1. 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 and the steering control ECU from overheating. If the temperatures of the motor and ECU drop, the system will return to normal.)

    3. The vehicle is exposed to extremely low temperatures. (If the ambient temperature becomes approximately -30°C, system control will be suspended.)

NOTICE:
If any of the above occurs, perform steering angle sensor initialization (Click here).