LANE-KEEPING ASSIST SYSTEM, Diagnostic DTC:C1A71

DTC Code DTC Name
C1A71 Power Steering Control Torque

DESCRIPTION

When the lane keeping assist system operates, the driving support ECU sends a signal to the power steering ECU to operate the power steering motor.

DTC Code DTC Detection Condition Trouble Area
C1A71

Either condition is met:


  • When the lane keeping assist main switch is on and the vehicle speed is 50 km/h (31 mph) or more, the target steering torque value sent by the driving support ECU to the power steering ECU is too high for electronic power steering control.

  • When the vehicle speed is 50 km/h (31 mph) or more with the lane-keeping assist main switch on, communication between the driving support ECU and power steering ECU is malfunctioning.

  • Power steering system

  • Driving support ECU

PROCEDURE


  1. CHECK FOR DTC (POWER STEERING SYSTEM)


    1. Check for DTCs Click here.

      OK
      Power steering system DTCs are not output.

    NG

    GO TO POWER STEERING SYSTEM Click here

    OK

  2. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Perform the following to make sure the DTC detection conditions are met.

      Tech Tips

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


      1. Drive the vehicle at a speed of 50 km/h (31 mph) or more.

      2. Turn the lane-keeping assist main switch on.

    3. Check for DTCs Click here.

      OK
      DTC C1A71 is not output.
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE DRIVING SUPPORT ECU Click here

    C

    REPLACE DRIVING SUPPORT ECU Click here