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Data List / Active Test [09/2014 - 10/2015]

  1. DATA LIST 

    HINT: 

    Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

    NOTE:

    In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

    1. Turn the power switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / EMPS / Data List.
    6. According to the display on the Techstream, read the Data List.
      EMPS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Meter Vehicle Velocity Vehicle speed from meter/
      Min.: 0.0 km/h (0.0 mph)
      Max.: 300.0 km/h (186.4 mph)      		 0 km/h (0 mph) The vehicle is stopped.
      No significant fluctuation The vehicle is driven at a constant speed.
      Motor Actual Current Amount of current supplied to motor/
      Min.: -327.68 A
      Max.: 327.67 A      		 Value changes in proportion to steering effort The power steering is in operation.
      Command Value Current Amount of current requested for motor/
      Min.: -327.68 A
      Max.: 327.67 A      		 Value changes in proportion to steering effort The power steering is in operation.
      Steering Angle Velocity Steering angle speed/
      Min.: -32768 deg/s
      Max.: 32767 deg/s      		 Value changes in proportion to steering speed The steering wheel is turned.
      Thermistor Temperature ECU substrate temperature/
      Min.: -50.0°C (-58.0°F)
      Max.: 150.0°C (302.0°F)      		 - -
      IG Power Supply ECU power source voltage/
      Min.: 0.0000 V
      Max.: 20.1531 V      		 11 to 14 V The power switch is on (IG).
      Steering Angle Sens Sig Steering sensor signal status/
      OK, NG(1), NG(2) or NG(3)      		 OK NG(1): The learning has not completed.
      NG(2): The steering sensor is abnormal.
      NG(3): There is a communication error.
      Torque Sensor 1 Output Torque sensor 1 rotation angle/
      Min.: 0.000 deg
      Max.: 1441.770 deg      		 Value changes from 0 to 360° every 45° of steering angle The steering wheel is turned.
      Torque Sensor 2 Output Torque sensor 2 rotation angle/
      Min.: 0.000 deg
      Max.: 1441.770 deg      		 Value changes from 0 to 360° every 45° of steering angle The steering wheel is turned.
      TRQ1 Zero Point Value Zero point value of torque sensor 1/
      Min.: 0.000 deg
      Max.: 1441.770 deg      		 Value differs depending on vehicle The steering wheel is not turned (without load).
      TRQ2 Zero Point Value Zero point value of torque sensor 2/
      Min.: 0.000 deg
      Max.: 1441.770 deg      		 Value differs depending on vehicle The steering wheel is not turned (without load).
      Steering Wheel Torque Steering torque/
      Min.: -327.68 Nm
      Max.: 7.00 Nm      		 Value changes in proportion to steering effort The steering wheel is turned.
      Motor Rotation Angle Motor rotation angle/
      Min.: 0.000 deg
      Max.: 1441.770 deg      		 Value changes from 0 to 360° The steering wheel is turned.
      Command Val Current 2 Amount of current requested for motor 2/
      Min.: -327.68 A
      Max.: 327.67 A      		 - -
      Motor Voltage Motor power source voltage/
      Min.: 0.000 V
      Max.: 98.000 V      		 Approximately 46 V The power steering is not in operation.
      Approximately 25 to 50 V The power steering is in operation.
      Motor Terminal Volt(U) Motor terminal voltage (U phase)/
      Min.: 0.000 V
      Max.: 98.000 V      		 0 to 50 V The power steering is in operation.
      Motor Terminal Volt(V) Motor terminal voltage (V phase)/
      Min.: 0.000 V
      Max.: 98.000 V      		 0 to 50 V The power steering is in operation.
      Motor Terminal Volt(W) Motor terminal voltage (W phase)/
      Min.: 0.000 V
      Max.: 98.000 V      		 0 to 50 V The power steering is in operation.
      IG ON/OFF Times Number of times power switch is turned on (IG) after DTC stored/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Motor Overheat Record Continuous overheat prevention control record/
      Unrec or Rec      		 - -
      Motor Lo Power Record PIG power source voltage drop record/
      Unrec or Rec      		 - -
      Str Angle Inter Record Record of steering sensor signal interruption/
      Unrec or Rec      		 - -
      Spd Sig Invalid Record Record of vehicle speed signal invalid/
      Unrec or Rec      		 - -
      Battery Voltage Lo Record Number of times auxiliary battery voltage is low/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Battery Control Count (Body ECU) Number of auxiliary battery load control operations/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Battery Voltage Auxiliary battery voltage/
      Min.: 0.0 V
      Max.: 25.5 V      		 11 to 14 V The power switch is on (IG).
      DC-DC Warning Signal Power steering converter warning signal/
      OK, NG(1) or NG(2)      		 OK  
      PS Assist Signal Power steering assist signal status/
      ON or OFF      		 - -
      Ready Status Ready status/
      OFF or Ready      		 Ready: READY ON
      OFF: Not READY ON      		  
      Motor Actual Current 2 Amount of current supplied to motor 2/
      Min.: -327.68 A
      Max.: 327.67 A      		 Value changes in proportion to steering effort The power steering is in operation.
      Torque Sensor 1 Avg(SIN) Torque sensor 1 average value (SIN phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Torque Sensor 1 Avg(COS) Torque sensor 1 average value (COS phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Torque Sensor 2 Avg(SIN) Torque sensor 2 average value (SIN phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Torque Sensor 2 Avg(COS) Torque sensor 2 average value (COS phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Rotation Angle Sens Avg(SIN) Rotation angle sensor average value (SIN phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Rotation Angle Sens Avg(COS) Rotation angle sensor average value (COS phase)/
      Min.: 0.0000 V
      Max.: 4.9725 V      		 - -
      Motor Overheat Limit Cnt(Normal) Number of times system was limited to prevent motor overheating (excluding times when there was a high load)/
      Min.: 0 times
      Max.: 255 times      		 - -
      Assist Limit Cnt(Power Voltage Low) Number of times system was limited when power source voltage was low/
      Min.: 0 times
      Max.: 255 times      		 - -
      Power Vol Low Prevention Limit Cnt Number of times system was limited to prevent low power source voltage/
      Min.: 0 times
      Max.: 255 times      		 - -
      Eng Stall/Ready OFF Cnt Number of times system was limited when the engine stalled or the system was in Ready OFF/
      Min.: 0 times
      Max.: 255 times      		 - -
      Motor Overheat Limit Cnt(Motor Overload) Number of times system was limited to prevent motor overheating when there was a high load/
      Min.: 0 times
      Max.: 255 times      		 - -
      DCDC Current Limit Cnt(DCDC Malf) Number of times current limited during power steering converter malfunction /
      Min.: 0 times
      Max.: 255 times      		 - -
      Assist Limit Cnt(Vehicle Spd Sig Malf) Number of times system was limited when there was a vehicle speed signal malfunction/
      Min.: 0 times
      Max.: 255 times      		 - -
      Battery Voltage Keep Limit Cnt Number of times system was limited to conserve auxiliary battery voltage/
      Min.: 0 times
      Max.: 255 times      		 - -
      Assist Limit Record 1 Power assist limitation record 1/
      Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, DC-DC Malf, Vhcl Spd Sig Malf or Batt Vol Keep      		 - -
      Record 1 Key Cycle Number of trip in which record 1 was stored/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Record 1 Key Cycle Elapsed Time Time elapsed from when power switch was turned on (IG) until record 1 was stored/
      Min.: 0.0 s
      Max.: 53687091.1 s      		 - -
      Assist Limit Record 2 Power assist limitation record 2/
      Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, DC-DC Malf, Vhcl Spd Sig Malf or Batt Vol Keep      		 - -
      Record 2 Key Cycle Number of trip in which record 2 was stored/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Record 2 Key Cycle Elapsed Time Time elapsed from when power switch was turned on (IG) until record 2 was stored/
      Min.: 0.0 s
      Max.: 53687091.1 s      		 - -
      Assist Limit Record 3 Power assist limitation record 3/
      Unrec, Mtr Overheat, Pow Vol Low, Pow Vol Low Prevent, Eng Stall, Ready OFF, Mtr Overload, DC-DC Malf, Vhcl Spd Sig Malf or Batt Vol Keep      		 - -
      Record 3 Key Cycle Number of trip in which record 3 was stored/
      Min.: 0 times
      Max.: 65535 times      		 - -
      Record 3 Key Cycle Elapsed Time Time elapsed from when power switch was turned on (IG) until record 3 was stored/
      Min.: 0.0 s
      Max.: 53687091.1 s      		 - -
      Steering Angle Steering angle/
      Min.: -3072.0 deg
      Max.: 3070.5 deg      		 - -
      The Number of DTCs Number of stored DTCs when freeze frame data is stored/
      Min.: 0
      Max.: 255      		 - -

      HINT: 

      • With the vehicle stopped or driving very slowly, if the steering wheel is turned repeatedly or turned to a lock position and the vehicle is driven for an extended period of time, the amount of power assist is decreased to prevent overheating of the motor and ECU. If this occurs, turn the power switch on (READY) and do not turn the steering wheel for approximately 10 minutes to improve power assist a little.
      • If the auxiliary battery is not sufficiently charged or the voltage decreases temporarily, the amount of power assist is reduced and the power steering warning light comes on. In such cases, the amount of power assist returns normal when the auxiliary battery voltage recovers.
      • When the value displayed for "Battery Control Count (Body ECU)" in the Data List is not 0 with the auxiliary battery voltage low, the system is limiting the seat heater, rear window defogger and windshield deicer operation. In this case, inspect the charging system (Refer to ON-VEHICLE INSPECTION [09/2014 - ] ).
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