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Electronic Power Steering System (Diagnostics - Introduction): Other Lexus GS III рестайлинг

Electronic Steering ~777 words

FREEZE FRAME DATA

  1. FREEZE FRAME DATA NOTE: It is difficult to show the specified values (judgment values) clearly because freeze frame data values change significantly due to differences in measurement conditions, surroundings or vehicle conditions. For this reason, there may be a problem even when the values are within specifications. Turn the power switch ON (IG) and park the vehicle on level ground. Check the freeze frame data by using the Techstream. Connect the Techstream to the DLC3. Turn the power switch ON (IG) and check the freeze frame data by following the prompts the Techstream display screen. Enter the following menus: Chassis / EMPS / Utility / Freeze Frame Data. Tester Display Measurement Item/Range Normal Condition Reference Value Torque Sensor 1 Output Torque sensor 1 rotation angle/ Min.: 0 deg, Max.: 360 deg Steering wheel is turned Value changes from 0 to 360° every 22.5° of steering angle Engine Revolution Engine revolution/ Min.: 0 RPM, Max.: 8192 RPM Engine is running at a constant speed No significant fluctuation Torque Sensor 2 Output Torque sensor 2 rotation angle/ Min.: 0 deg, Max.: 360 deg Steering wheel is turned Value changes from 0 to 360° every 22.5° of steering angle Meter Vehicle Velocity Vehicle speed from meter/ Min.: 0 km/h (0 mph), Max.: 255 km/h (158 mph) Vehicle is stopped 0 km/h (0 mph) Vehicle is driven at a constant speed No significant fluctuation Motor Actual Current Amount of current to motor/ Min.: -128 A, Max.: 127 A Power steering is in operation Value changes in proportion to steering effort Command Value Current Demanded amount of current to motor/ Min.: -128 A, Max.: 127 A Power steering is in operation Value changes in proportion to steering effort Steering Angle Velocity Steering angle speed/ Min.: -4096 deg/sec, Max.: 4064 deg/sec Steering wheel is turned Value changes in proportion to steering speed Thermistor Temperature ECU substrate temperature/ Min.: -50 °C, Max.: 205°C Power switch ON (IG) - PIG Power Supply Power source voltage to activate motor/ Min.: 0 V, Max.: 25.5 V Power steering is in operation 10 to 14 V IG Power Supply ECU power source voltage/ Min.: 0 V, Max.: 25.5 V Power switch ON (IG) 10 to 14 V TRQ1 Zero Point Value Zero point value of torque sensor 1/ Min.: 0 deg, Max.: 360 deg Steering wheel is not turned (without load) Values differ depending on vehicle TRQ2 Zero Point Value Zero point value of torque sensor 2/ Min.: 0 deg, Max.: 360 deg Steering wheel is not turned (without load) Values differ depending on vehicle Steering Wheel Torque Steering torque/ Min.: -7.0 N*m, Max.: 7.0 N*m Power switch ON (IG) Steering wheel is turned Value changes in proportion to steering effort Motor Rotation Angle Motor rotation angle/ Min.: 0 deg, Max.: 360 deg Steering wheel is turned During steering operation, motor rotation angle value changes from 0 to 360° Command Val Current 2 Demanded amount of current to motor 2/ Min.: -128 A, Max.: 127 A Power steering is in operation Value changes in proportion to steering effort PIG2 Voltage Coil rear pressurization voltage/ Min.: 0 V, Max.: 64 V Power steering is in operation 10 to 15 V Motor Voltage Motor power source voltage/ Min.: 0 V, Max.: 64 V Power steering is in operation 27 to 34 V Motor Terminal Volt (U) Motor terminal voltage (U phase)/ Min.: 0 V, Max.: 64 V Steering wheel is not turned 12 to 15 V Steering wheel is turned 2 to 34 V Motor Terminal Volt (V) Motor terminal voltage (V phase)/ Min.: 0 V, Max.: 64 V Steering wheel is not turned 12 to 15 V Steering wheel is turned 2 to 34 V Motor Terminal Volt (W) Motor terminal voltage (W phase)/ Min.: 0 V, Max.: 64 V Steering wheel is not turned 12 to 15 V Steering wheel is turned 2 to 34 V

FAIL-SAFE CHART

If a problem occurs in the electronic power steering system, the P/S warning light will come on in the combination meter and steering power assistance will be stopped, fixed at a particular point, or decreased simultaneously to protect the system.

DTC No.MalfunctionFail-safe
C1511Torque Sensor Circuit MalfunctionPower assistance stops.
C1512
C1513
C1521Motor Circuit Malfunction
C1522
C1523
C1524
C1528Motor Rotation Angle Sensor Malfunction
C1531ECU Malfunction
C1532
C1554Power Supply Relay Failure
C1555Motor Relay Welding Failure
C1533ECU MalfunctionSystem overheat prevention control continues without using the substrate temperature sensor.
C1534ECU MalfunctionTorque sensor zero point and rotation angle sensor calibration value set to the default values.
C1541Vehicle Speed Signal MalfunctionAmount of power assistance is fixed for a speed of 100 km/h (62 mph).
U0129Lost Communication With Skid Control ECU
C1567Lost Communication between EPS ECU and VGRS ECUEPS cooperative control stops.
U0130Lost Communication with VGRS
U0293Lost Communication with HV ECU

HINT

The amount of power assistance may be decreased to prevent the motor and ECUs from overheating if the steering wheel is continuously turned when the vehicle is either stopped or driven at a low speed, or if the steering wheel is kept at either full lock position for a long time. In that case, the amount of power assistance will return to normal if the steering wheel is not turned for approximately 10 minutes with the engine idling.