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Home >> Toyota >> 2013 >> Matrix Base, Automatic Trans >> Repair and Diagnosis (Single Page) >> Steering >> Power Steering >> Power Steering System (Diagnostic Codes & Circuit Tests) >> Power Steering System >> DTC C1581: Assist Map Number Un-Writing >> Procedure
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DTC C1581: Assist Map Number Un-Writing: Procedure

  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 → See step   2 

    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 → See step   4 

    OK → See step   3 

  3. REPLACE POWER STEERING ECU. Refer to  REMOVAL 
  4. GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING