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Home >> Lexus >> 2007 >> LS 460L >> Repair and Diagnosis >> Steering >> Power Steering >> Power Steering System >> DTC C1581 Assist Map Number Un-Writing >> Inspection Procedure
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Inspection Procedure

  1. PERFORM ASSIST MAP WRITING 
    1. Turn the engine switch on (IG), and wait for 30 seconds or more.

      HINT:

      The assist map is automatically written when approximately 30 seconds have elapsed after the engine switch is turned on (IG). DTC C1581 will be cleared after the assist map is written.

    2. Check for DTCs.

      Result 

      ASSIST MAP WRITING

      DTC Condition Proceed to
      DTC C1581 is output A
      DTC C1581 is not output B

    B: END 

    A: GO TO NEXT STEP 

  2. CHECK CAN COMMUNICATION SYSTEM 
    1. Using the intelligent tester, check for DTCs and confirm that there are no problems in the CAN communication system (see DIAGNOSIS SYSTEM ).

      Result 

      CAN COMMUNICATION SYSTEM

      DTC Condition Proceed to
      DTC is not output A
      DTC is output B

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

    A: GO TO NEXT STEP 

  3. CHECK SUSPENSION CONTROL ECU 
    1. Check if a suspension control ECU that complies with the vehicle's specifications is installed.

      OK : 

      Suspension control ECU that complies with vehicle's specifications is installed. 

      NOTE: If replacing the power steering ECU, initialize the rotation angle sensor value and calibrate the torque sensor zero point (see CALIBRATION  ).

    NG: REPLACE SUSPENSION CONTROL ECU  (See REMOVAL )

    OK: REPLACE POWER STEERING ECU (See  REMOVAL   )