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Home >> Lexus >> 2018 >> NX 300 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Lane Departure Alert System (W/ Steering Control) - Diagnostic Codes & Symptom Tests >> LANE DEPARTURE ALERT SYSTEM (w/ Steering Control) >> DTC C1A71: Power Steering Control Torque [10/2014 - 09/2017] >> Procedure
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DTC C1A71: Power Steering Control Torque [10/2014 - 09/2017]: Procedure

  1. CHECK FOR DTCs (POWER STEERING SYSTEM) 
    1. For Manual Tilt and Manual Telescopic Steering Column:
      1. Clear the DTCs.

        Refer to DTC CHECK / CLEAR [10/2014 - 05/2019]

        Chassis > EMPS > Clear DTCs 

      2. Make sure that the DTC detection conditions are met.

        HINT: 

        If the detection conditions are not met, the system cannot detect the malfunction.

      3. Check for DTCs.

        Refer to DTC CHECK / CLEAR [10/2014 - 05/2019]

        Chassis > EMPS > Trouble Codes 

    2. For Power Tilt and Power Telescopic Steering Column:
      1. Clear the DTCs.

        Refer to DTC CHECK / CLEAR [10/2014 - 05/2019]

        Chassis > EMPS > Clear DTCs 

      2. Make sure that the DTC detection conditions are met.

        HINT: 

        If the detection conditions are not met, the system cannot detect the malfunction.

      3. Check for DTCs.

        Refer to DTC CHECK / CLEAR [10/2014 - 05/2019]

        Chassis > EMPS > Trouble Codes 

      Result

      Result Proceed to
      Power steering system DTCs are not output A
      Power steering system DTCs are output (for Manual Tilt and Manual Telescopic Steering Column) B
      Power steering system DTCs are output (for Power Tilt and Power Telescopic Steering Column) C

    Result: 

    GO TO POWER STEERING SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - ] 

    Result: 

    GO TO POWER STEERING SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - ] 

    Result: 

    See step  2

  2. CHECK FOR DTCs 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Chassis > Lane Departure Alert > Clear DTCs 

    2. Make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Chassis > Lane Departure Alert > Trouble Codes 

      Result

      Result Proceed to
      DTC C1A71 is not output A
      DTC C1A71 is output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - 09/2017] 

    Result: 

    See step  3

  3. REPLACE LANE DEPARTURE WARNING CAMERA 
    1. Replace the lane departure warning camera.

      Refer to REMOVAL [10/2014 - 09/2017]

    2. Perform the lane departure warning camera adjustment.

      Refer to ADJUSTMENT [10/2014 - 09/2017]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. CHECK FOR DTCs 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Chassis > Lane Departure Alert > Clear DTCs 

    2. Make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Chassis > Lane Departure Alert > Trouble Codes 

      Result

      Result Proceed to
      DTC C1A71 is not output A
      DTC C1A71 is output (for Manual Tilt and Manual Telescopic Steering Column) B
      DTC C1A71 is output (for Power Tilt and Power Telescopic Steering Column) C

    Result: 

    END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE) 

    Result: 

    REPLACE POWER STEERING ECU ASSEMBLY. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - ] 

    Result: 

    REPLACE POWER STEERING ECU ASSEMBLY. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - ]