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VARIABLE GEAR RATIO STEERING SYSTEM, Diagnostic DTC:C1597

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DTC Code DTC Name
C1597 Lost Communication between VGRS and DRS
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DESCRIPTION

The VGRS ECU (front steering control ECU) communicates with the DRS ECU (rear steering control ECU) via the local bus.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Return-to-normal Condition
C1597 Lost Communication between VGRS and DRS

All conditions are met:


  • 1 second or more elapse after turning the power switch on (IG).

  • Power source voltage at 10 to 16 V.

  • A problem is detected with the DRS ECU (rear steering control ECU) via CAN communication for approximately 3 seconds or more.

  • VGRS ECU (front steering control ECU)

  • DRS ECU (rear steering control ECU)

  • Harness or connector

 Comes on Power switch on (IG) again
Table 1. *1 VGRS ECU (Front Steering Control ECU) *2 DRS ECU (Rear Steering Control ECU)
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WIRING DIAGRAM

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CAUTION / NOTICE / HINT

Note:

  • When replacing the DRS ECU (rear steering control ECU), perform neutral position memorization and motor rotation angle sensor calibration.

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  • When replacing the VGRS ECU (front steering control ECU), perform actuator angle neutral position calibration and initialization after replacement.

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PROCEDURE


  1. Click here

    CHECK FOR DTC (DYNAMIC REAR STEERING SYSTEM)


    1. Check for DTCs in the dynamic rear steering system.

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      1. Chassis > DRS > Trouble Codes


      Result
      Result Proceed to
      DTC U0130 is not output A
      DTC U0130 is output B

  2. Click here

    CHECK FOR DTC


    1. Check for DTCs.

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      1. Chassis > VGRS > Trouble Codes


      Result
      Result Proceed to
      DTC U0134 is not output A
      DTC U0134 is output B

  3. Click here

    CHECK HARNESS AND CONNECTOR (CAN+, CAN- TERMINAL)


    1. Turn the power switch off.

    2. Check the connection condition of the VGRS ECU (front steering control ECU) connector and terminals.

    3. Disconnect the G79 VGRS ECU (front steering control ECU) connector.

    4. Measure the resistance according to the value(s) in the table below.

      Tip:

      Measure the resistance of the wire harness and DRS ECU (rear steering control ECU) at the VGRS ECU (front steering control ECU) connector.

      Table 2. Standard Resistance
      Tester Connection Condition Specified Condition
      G79-10 (CAN+) - G79-11(CAN-) Always 100 to 140 Ω
      G79-10 (CAN+) - Body ground Always 100 kΩ or higher
      G79-11 (CAN-) - Body ground Always 100 kΩ or higher
      Result
      Proceed to
      OK
      NG

  4. Click here

    INSPECT VGRS ECU (FRONT STEERING CONTROL ECU) (CAN+, CAN- TERMINAL)


    1. Turn the power switch off.

    2. Disconnect the G79 VGRS ECU (front steering control ECU) connector.

    3. B004S58C13
      *a

      Component without harness connected

      (VGRS ECU [Front Steering Control ECU])

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

      Table 3. Standard Resistance
      Tester Connection Condition Specified Condition
      G79-10 (CAN+) - G79-11(CAN-) Always 100 to 140 Ω
      G79-10 (CAN+) - Body ground Always 100 kΩ or higher
      G79-11 (CAN-) - Body ground Always 100 kΩ or higher
      Result
      Proceed to
      OK
      NG

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    RECONFIRM DTC


    1. Reconnect the G79 VGRS ECU (front steering control ECU) connector.

    2. Clear the DTCs.

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      1. Chassis > VGRS > Clear DTCs


    3. Check for DTCs.

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      1. Chassis > VGRS > Trouble Codes


      Result
      Result Proceed to
      DTC C1597 is not output A
      DTC C1597 is output B

    • A

      USE SIMULATION METHOD TO CHECKClick here

    • B

      REPLACE VGRS ECU (FRONT STEERING CONTROL ECU)Click here

  6. Click here

    INSPECT DRS ECU (REAR STEERING CONTROL ECU) (CAN+, CAN- TERMINAL)


    1. Turn the power switch off.

    2. Disconnect the P4 DRS ECU (rear steering control ECU) connector.

    3. B004RVDC13
      *a

      Component without harness connected

      (DRS ECU [Rear Steering Control ECU])

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

      Table 4. Standard Resistance
      Tester Connection Condition Specified Condition
      P4-11 (CAN+) - P4-8 (CAN-) Always 100 to 140 Ω
      P4-11 (CAN+) - Body ground Always 100 kΩ or higher
      P4-8 (CAN-) - Body ground Always 100 kΩ or higher
      Result
      Proceed to
      OK
      NG

    • OK

      REPAIR OR REPLACE HARNESS OR CONNECTOR

    • NG

      REPLACE DRS ECU (REAR STEERING CONTROL ECU)Click here