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Inspection Procedure

NOTE: If the steering column or power steering ECU is replaced, perform rotation angle sensor initialization and torque sensor zero point calibration (See CALIBRATION  ).
  1. PERFORM ASSIST MAP WRITING 
    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / EMPS / Utility / Signal Check. Switch the power steering system to the test mode by following the display on the Techstream.
    6. Wait for 1 second or more.
    7. Turn the ignition switch off.
    8. Turn the ignition switch to ON.
    9. Check for DTCs.

      HINT:

      Approximately 1 second after switching the test mode, assist map writing is automatically performed. After the automatic assist map writing, DTC C1581 is cleared.

      OK: 

      DTC C1581 is not output  .

      NG: Go to Next Step 

      OK: END (COMPLETION OF ASSIST MAP WRITING RETURNS SYSTEM TO NORMAL) 

  2. CHECK DTC (CAN COMMUNICATION SYSTEM) 
    1. Check for DTCs.

      OK: 

      DTC is not output  .

      NG: GO TO CAN COMMUNICATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

      OK: REPLACE POWER STEERING ECU  (See POWER STEERING ECU  )