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Home >> Toyota >> 2018 >> Corolla L >> Repair and Diagnosis >> Steering >> Steering Control Systems >> Lane Departure Alert System (W/ Steering Control) - Diagnostic Codes & Circuit Tests (Model Code: ZRE172) >> LANE DEPARTURE ALERT SYSTEM (W/ Steering Control) >> DTC C1A71: Power Steering Control Torque [08/2016 - ] >> Procedure
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DTC C1A71: Power Steering Control Torque [08/2016 - ]: Procedure

  1. CHECK FOR DTCs (POWER STEERING SYSTEM) 

    HINT: 

    Lane departure alert system DTC C1A71 may be stored due to a malfunction in the power steering system. Therefore it is necessary to check for and troubleshoot power steering system DTCs first.

    1. Check for DTCs are output.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Chassis > EMPS > Trouble Codes 

      Result

      Result Proceed to
      Power steering system DTCs are not output A
      Power steering system DTCs are output B

    Result:  2

    GO TO POWER STEERING SYSTEM:  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - ] 

    Result:  1

    See step  2

  2. CHECK FOR DTCs (LANE DEPARTURE ALERT SYSTEM) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Chassis > LKA/LDA > Clear DTCs 

    2. Perform the following procedure.

      HINT: 

      If the following procedure is not performed, the previously output DTC cannot be detected.

      1. Turn the ignition switch to ON and wait 7 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Chassis > LKA/LDA > Trouble Codes 

      Result

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

    Result:  1

    USE SIMULATION METHOD TO CHECK:  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 08/2017]  , HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - ] 

    Result:  2

    See step  3

  3. REPLACE FORWARD RECOGNITION CAMERA 
    1. Replace the forward recognition camera.

      Refer to REMOVAL [08/2016 - ]

    2. Perform forward recognition camera adjustment.

      Refer to ADJUSTMENT (SEQUENTIAL RECOGNITION) [08/2016 - ]

      Result

      Proceed to
      NEXT

    Result:  2

    NEXT 

    See step  4

  4. CHECK FOR DTCs (LANE DEPARTURE ALERT SYSTEM) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Chassis > LKA/LDA > Clear DTCs 

    2. Perform the following procedure.

      HINT: 

      If the following procedure is not performed, the previously output DTC cannot be detected.

      1. Turn the ignition switch to ON and wait 7 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2016 - ]

      Chassis > LKA/LDA > Trouble Codes 

      Result

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

    Result:  1

    END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE) 

    Result:  2

    REPLACE POWER STEERING ECU ASSEMBLY:  COMPONENTS [08/2013 - ]