AIR SUSPENSION SYSTEM, Diagnostic DTC:C1784

DTC Code DTC Name
C1784 Steering Angle Sensor Communication Error

DESCRIPTION

The steering angle sensor signal is sent to the suspension control ECU through the CAN communication system. When there is a communication malfunction, it will be detected by the diagnosis function.

DTC No. Detection Condition Trouble Area
C1784 Steering angle sensor signal malfunction is detected, or steering angle sensor power malfunction signal is detected for 5 seconds or more

  • Steering angle sensor

  • Steering angle sensor power source circuit

  • Suspension control ECU

WIRING DIAGRAM

A01GYUSE03

INSPECTION PROCEDURE

Note


  • Before performing troubleshooting, inspect the connectors of related circuits.

  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first Click here.

  • Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation Click here; 2) DTC inspection; and 3) intelligent tester inspection (Data List or Active Test). If no malfunctions are found in other areas, replace the suspension control ECU.

  • If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed Click here.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTC Click here.

    2. Perform a road test.

    3. Check if DTC C1784 and U0126 are output Click here.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD) B
      DTC is output (for RHD) C

    B

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    C

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

    A

  2. CHECK DTC (BRAKE CONTROL SYSTEM)


    1. Check if DTC C1231/31 is output Click here.

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

    B

    GO TO BRAKE CONTROL SYSTEM (DIAGNOSTIC TROUBLE CODE CHART) Click here

    A

  3. CHECK STEERING ANGLE SENSOR (POWER SOURCE)


    1. A01H0V4E02

      Disconnect the L21 sensor connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      L21-1 (IG) - Body ground Power switch ON (IG) 11 to 14 V
      Standard resistance
      Tester Connection Condition Specified Condition
      L21-2 (ESS) - Body ground Always Below 1 Ω

    3. Check that the steering angle sensor's connector is not deformed or corroded.

      OK
      No deformation or corrosion.

      Tech Tips

      If the steering angle sensor's connector is defective, replace the sensor.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK STEERING ANGLE SENSOR (DATA LIST)


    1. Turn the power switch OFF.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the power switch ON (IG) and the tester ON.

    4. Enter the following menus: Chassis / Air suspension / Data List.

    5. Check the values by referring to the table below.

      Air suspension
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Steering Angle

      Steering angle sensor reading /

      min.: -49152.0 deg

      max.: 49150.5 deg

      Actual steering angle

      Left turn: reading increases

      Right turn: reading decreases

      		 -
      OK
      Steering wheel turning angle value changes.
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    B

    REPLACE SUSPENSION CONTROL ECU Click here

    C

    REPLACE SUSPENSION CONTROL ECU Click here

    A

    REPLACE STEERING ANGLE SENSOR Click here