Variable Gear Ratio Steering System (Diagnostic Codes & Symptom Tests): Overview Lexus LX J200 рестайлинг

DESCRIPTION

If the steering control ECU or steering actuator is replaced, or if the tie-rod ends are adjusted, VGRS system calibration is required. If the steering control ECU detects that steering angle adjustment is incomplete, it will store DTC C1591/51.

The steering control ECU first checks the actuator angle neutral position calibration flag after entering test mode. If the ECU detects that steering actuator angle neutral position calibration is incomplete twice, it will store DTC C1592/52.

If the steering control ECU detects a steering actuator standard position error, it will store DTC C1593/53.

Signal transmission between the steering control ECU and steering angle sensor is performed via serial communication.

If an error occurs between them in serial communication, the ECU will store DTC C1595/55.

HINT

*: A tire angle of 36° and a motor rotation angle of 36° correspond to the steering wheel angle. The amount of change in tire angle and motor rotation angle is from when the mode is changed to test mode.

Scheme 115

The steering control ECU drives the actuator while the steering wheel is turned to set the gear ratio. It detects the current flowing into the actuator motor driving circuit.

If the steering control ECU detects excessive current, it will store DTC C15A1/61, turn on the master warning light, and stop VGRS operation.

Scheme 116

The steering control ECU drives the actuator based on steering angle sensor signals and vehicle speed signals.

If the steering control ECU detects excessive current flowing into the steering actuator, or an internal malfunction, it will turn on the master warning light, store DTC C15A2/62, and stop VGRS operation.

If the steering control ECU detects a malfunction in the motor drive circuit, it will turn the master warning light on, store DTC C15A6/62, and stop VGRS operation.

Scheme 117

The steering actuator drives the internal motor using the current output from the steering control ECU to change the relative angle between the tire angle and steering wheel angle.

The rotation angle sensor in the steering actuator detects the motor rotation angle and outputs this information to the steering control ECU.

If the steering control ECU detects a malfunction in the rotation angle sensor circuit, it will store DTC C15A3/63.

HINT

*: A tire angle of 36° and a motor rotation angle of 36° correspond to the steering wheel angle. The amount of change in tire angle and motor rotation angle is from when the mode is changed to test mode.

Scheme 118

When the VGRS system is normal, the steering actuator conducts current from the steering control ECU to the steering actuator solenoid to release the lock mechanism, enabling motor operation.

The steering actuator does not operate under any of the following conditions

1. The engine switch is off.
2. The motor in the actuator is locked by the lock mechanism to prevent rotation (fail-safe function).
3. The system is being protected from overheating (fail-safe function).

If the steering control ECU detects a malfunction in the steering actuator lock mechanism or a motor rotation angle error, it will store these DTCs.

If the steering control ECU detects a malfunction in the lock mechanism, it will turn the master warning light on, store DTC C15A5/65, and stop VGRS operation.

Scheme 119

If the steering control ECU detects an internal malfunction, it will turn the master warning light on, store these DTCs, and stop VGRS operation.

If the steering control ECU detects an internal malfunction, it will turn the master warning light on, store DTC C15B4/71, and stop VGRS operation.

The steering control ECU detects a steering angle sensor malfunction by receiving an error signal from the steering angle sensor via CAN communication. If the steering control ECU detects this error signal, it will turn the master warning light on, store these DTCs, and stop VGRS operation.

Scheme 120

The steering control ECU detects a vehicle speed error by receiving an error signal from the skid control ECU via CAN communication.

If the steering control ECU detects this error signal, it will turn the master warning light on, store this DTC, and stop VGRS operation.

The steering control ECU monitors the IG power supply voltage.

If the steering control ECU detects a malfunction, it will turn on the master warning light, store DTC C15C6/77, and stop VGRS operation.

Scheme 121

The steering control ECU monitors PIG (motor power source voltage) and detects a malfunction in the power supply relay (located inside the steering control ECU).

If the steering control ECU detects a malfunction, it will turn on the master warning light, store these DTCs, and stop VGRS operation.

Scheme 122

The steering control ECU receives signals from the skid control ECU, ECM and steering angle sensor via CAN communication. When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system first.

If the steering control ECU detects that the VGRS system has a malfunction, warning information is transmitted to the combination meter via CAN communication.

The combination meter will turn the master warning light on based on this information.

Warning information is transmitted via the following route

1. Steering control ECU --> (CAN) --> Network gateway ECU --> (CAN) --> Combination meter

Connecting terminals TC and CG of the DLC3 makes the master warning light blink and outputs DTCs.

Scheme 123

See also:
• REMOVAL [01/2012 - ]
• REMOVAL [01/2012 - ]
• ADJUSTMENT [01/2012 - ]
• INSPECTION [01/2012 - ]