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Fail-Safe Chart

  1. FAIL-SAFE CHART 

    This function minimizes the loss of the ECT functions when a malfunction occurs in each sensor or solenoid.

    FAIL-SAFE CHART

    Malfunctioning Part Function
    DTC P0500: Output Speed Sensor (SP2) During an output speed sensor malfunction, shift control is effected through the input speed sensor signal (NT).
    During an output speed sensor malfunction, up-shift to the 5th and 6th, AI-SHIFT*1 and flex lock up clutch control are prohibited.
    DTC P0717: Input Speed Sensor (NT) During an input speed sensor malfunction, shift control is effected through the output speed sensor signal (SP2).
    During an input speed sensor malfunction, up-shift to the 5th and 6th, AI-SHIFT*1 and flex lock up clutch control are prohibited.
    DTC P0710, P0712, P0713: ATF Temperature Sensor During an ATF temperature sensor malfunction, up-shift to the 5th and 6th and flex lock up clutch control are prohibited.
    Shift Solenoid Valve S1, S2, S3, S4 and SR The current to the failed solenoid valve is cut off and control is effected by operating the other solenoid valves.
    Shift control is effected depending on the failed solenoid as described in the table below.
    DTC P0748, P0778: Shift Solenoid Valve SL1 and SL2 During a solenoid valve SL1 or SL2 malfunction, up-shift to the 5th and 6th and flex lock up clutch control are prohibited.
    DTC P2714, P2716: Shift Solenoid Valve SLT During a solenoid valve SLT malfunction, the current to the solenoid valve is stopped. This stops line pressure optimal control, the shift shock increases. However, shifting is effected through normal clutch pressure control.
    DTC P2757, P2759: Shift Solenoid Valve SLU During a solenoid valve SLU malfunction, the current to the solenoid valve is stopped. This stops lock up control and flex lock up control, fuel economy decreases.
    HINT:
    *1: Artificial Intelligence Shift (AI-SHIFT) control In addition to the switching of the shift pattern through the pattern select switch, the AI-SHIFT control enables the ECM to estimate the road conditions and the driver's intention in order to automatically select the optimal shift pattern.
    1. Fail-safe operation for electronically malfunctioning shift solenoid valve (S1, S2, S3, S4 and SR).

      HINT:

      Fail-safe operation in the event of an electric system malfunction. Fail-safe function:

      If either of the shift solenoid valve circuits has an open or short failure, the ECM turns the other shift solenoid "ON" and "OFF" in order to shift into the gear positions shown in the table below. In case of an open or short circuit, the ECM stops sending the current to the open or short circuit solenoid.

      Even if starting the engine again in the fail-safe mode, the gear position remains in the same position.

      Fail-safe chart for electrical malfunction: 

      FAIL-SAFE CHART

      Shift Lever Position Normal
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 1st OFF ON ON OFF ON OFF ON
      2nd ON ON ON OFF ON OFF ON
      3rd ON OFF ON OFF ON OFF ON
      4th ON OFF OFF OFF ON OFF ON
      5th ON OFF OFF ON OFF ON OFF
      6th ON ON OFF ON OFF ON OFF
      S5 1st OFF ON ON OFF ON OFF ON
      2nd ON ON ON OFF ON OFF ON
      3rd ON OFF ON OFF ON OFF ON
      4th ON OFF OFF OFF ON OFF ON
      5th ON OFF OFF ON OFF ON OFF
      S4 1st OFF ON ON OFF ON OFF ON
      2nd ON ON ON OFF ON OFF ON
      3rd ON OFF ON OFF ON OFF ON
      4th ON OFF OFF OFF ON OFF ON
      S3 1st OFF ON ON OFF ON OFF ON
      2nd ON ON ON OFF ON OFF ON
      3rd (E/B) ON OFF ON OFF ON OFF OFF
      S2 1st OFF ON ON OFF ON OFF ON
      2nd (E/B) ON ON ON ON ON OFF OFF
      S1 1st (E/B) OFF ON ON OFF ON OFF OFF
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
      FAIL-SAFE CHART

      Shift Lever Position Shift Solenoid Valve S1 Electrical Malfunction (P0973, P0974)
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 1st X ON ON OFF ON OFF ON
      1st → 4th X ON → OFF ON → OFF OFF ON OFF ON
      3rd → 4th X OFF ON → OFF OFF ON OFF ON
      4th X OFF OFF OFF ON OFF ON
      5th X OFF OFF ON OFF ON OFF
      N → 5th X ON → OFF OFF ON OFF ON OFF
      S5 1st X ON ON OFF ON OFF ON
      1st → 4th X ON → OFF ON → OFF OFF ON OFF ON
      3rd → 4th X OFF ON → OFF OFF ON OFF ON
      4th X OFF OFF OFF ON OFF ON
      5th X OFF OFF ON OFF ON OFF
      S4 1st X ON ON OFF ON OFF ON
      1st → 4th X ON → OFF ON → OFF OFF ON OFF ON
      3rd → 4th X OFF ON → OFF OFF ON OFF ON
      4th X OFF OFF OFF ON OFF ON
      S3 1st X ON ON OFF ON OFF ON
      1st → 4th X ON → OFF ON → OFF OFF ON OFF ON
      3rd (E/B) → 4th X OFF ON → OFF OFF ON OFF OFF → ON
      S2 1st X ON ON OFF ON OFF ON
      1st (E/B) → 4th X ON → OFF ON → OFF OFF ON OFF OFF → ON
      S1 1st (E/B) X ON ON OFF ON OFF OFF
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
      FAIL-SAFE CHART

      Shift Lever Position Shift Solenoid Valve S2 Electrical Malfunction (P0976, P0977)
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 3rd OFF → ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      4th ON X OFF OFF ON OFF ON
      5th ON X OFF ON OFF ON OFF
      5th ON X OFF ON OFF ON OFF
      S5 3rd OFF → ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      4th ON X OFF OFF ON OFF ON
      5th ON X OFF ON OFF ON OFF
      S4 3rd OFF → ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      3rd ON X ON OFF ON OFF ON
      4th ON X OFF OFF ON OFF ON
      S3 3rd → 3rd (E/B) OFF → ON X ON OFF ON ON → OFF OFF
      3rd → 3rd (E/B) ON X ON OFF ON ON → OFF OFF
      3rd (E/B) ON X ON OFF ON OFF OFF
      S2 3rd → 3rd (E/B) OFF → ON X ON OFF ON ON → OFF OFF
      3rd (E/B) ON X ON OFF ON OFF OFF
      S1 3rd (E/B) OFF → ON X ON OFF ON OFF OFF
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
      FAIL-SAFE CHART

      Shift Lever Position Shift Solenoid Valve S3 Electrical Malfunction (P0979, P0980)
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 3rd → 4th OFF → ON ON → OFF X OFF ON OFF ON
      4th ON ON → OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      5th ON OFF X ON OFF ON OFF
      6th ON ON X ON OFF ON OFF
      S5 3rd → 4th OFF → ON ON → OFF X OFF ON OFF ON
      4th ON ON → OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      5th ON OFF X ON OFF ON OFF
      S4 3rd → 4th OFF → ON ON → OFF X OFF ON OFF ON
      4th ON ON → OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF ON
      S3 3rd → 4th OFF → ON ON → OFF X OFF ON OFF ON
      4th ON ON → OFF X OFF ON OFF ON
      4th ON OFF X OFF ON OFF OFF → ON
      S2 3rd → 4th OFF → ON ON → OFF X OFF ON OFF ON
      6th → 4th ON ON → OFF X OFF ON OFF OFF → ON
      S1 1st (E/B) → 4th OFF → ON ON → OFF X OFF ON OFF OFF → ON
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
      FAIL-SAFE CHART

      Shift Lever Position Shift Solenoid Valve S4 Electrical Malfunction (P0982, P0983)
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 1st OFF ON ON X ON OFF ON
      2nd ON ON ON X ON OFF ON
      3rd ON OFF ON X ON OFF ON
      4th ON OFF OFF X ON OFF ON
      4th ON OFF OFF X OFF → ON ON → OFF OFF → ON
      4th ON ON → OFF OFF X OFF → ON ON → OFF OFF → ON
      S5 1st OFF ON ON X ON OFF ON
      2nd ON ON ON X ON OFF ON
      3rd ON OFF ON X ON OFF ON
      4th ON OFF OFF X ON OFF ON
      4th ON OFF OFF X OFF → ON ON → OFF OFF → ON
      S4 1st OFF ON ON X ON OFF ON
      2nd ON ON ON X ON OFF ON
      3rd ON OFF ON X ON OFF ON
      4th ON OFF OFF X ON OFF ON
      S3 1st OFF ON ON X ON OFF ON
      2nd ON ON ON X ON OFF ON
      3rd (E/B) ON OFF ON X ON OFF OFF
      S2 1st OFF ON ON X ON OFF ON
      2nd (E/B) ON ON ON X ON OFF OFF
      S1 1st (E/B) OFF ON ON X ON OFF OFF
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
      FAIL-SAFE CHART

      Shift Lever Position Shift Solenoid Valve SR Electrical Malfunction (P0985, P0986)
      Gear*2 Shift solenoid (ECM output)
      S1 S2 S3 S4 SR SL1 SL2
      D, S6 1st OFF ON ON OFF X OFF ON
      2nd ON ON ON OFF X OFF ON
      3rd ON OFF ON OFF X OFF ON
      4th ON OFF OFF OFF X OFF ON
      5th ON OFF OFF ON X ON OFF
      6th ON ON OFF ON X ON OFF
      S5 1st OFF ON ON OFF X OFF ON
      2nd ON ON ON OFF X OFF ON
      3rd ON OFF ON OFF X OFF ON
      4th ON OFF OFF OFF X OFF ON
      5th ON OFF OFF ON X ON OFF
      S4 1st OFF ON ON OFF X OFF ON
      2nd ON ON ON OFF X OFF ON
      3rd ON OFF ON OFF X OFF ON
      4th ON OFF OFF OFF X OFF ON
      S3 1st OFF ON ON OFF X OFF ON
      2nd ON ON ON OFF X OFF ON
      3rd ON OFF ON OFF X OFF OFF
      S2 1st OFF ON ON OFF X OFF ON
      2nd ON ON ON OFF X OFF OFF
      S1 1st OFF ON ON OFF X OFF OFF
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • X: OFF (the ECM stops sending current to a malfunctioning solenoid valve)
      • →: For electrical malfunction, the ON/OFF condition is shown to the left of the "→".
      • →: For fail-safe mode, the ON/OFF condition is shown to the right of the "→".
      • E/B: Engine brake.
    2. Fail-safe operation for mechanical malfunction.

      HINT:

      Fail-safe operation in the event of a mechanical system malfunction.

      Fail-safe function:

      The ECM controls the gear position as shown in the table below when malfunctions occur.

      Fail-safe chart for mechanical malfunction: 

      FAIL-SAFE CHART

      DTC Condition Gear*2
      - Normal 1st 2nd 3rd 4th 5th 6th
      P0751 Shift solenoid valve S1: Stuck OFF malfunction 1st*3 1st*3 3rd 3rd 3rd 3rd
      P0761 Shift solenoid S3: Stuck ON malfunction 1st 2nd 3rd 3rd 3rd 3rd
      P0766 Shift solenoid valve S4, Shift solenoid valve SL2 or Valve body (brake control valve): Malfunction 1st 2nd 3rd 3rd 3rd 3rd
      P0781 Valve body (1-2 shift valve): Malfunction 1st*3 1st*3 3rd 3rd 3rd 3rd
      P0729 Valve body (sequence valve): Malfunction 1st 2nd 3rd 3rd 3rd 3rd
      HINT:
      • *2: Actual gear shift (gear position) under fail-safe operation.
      • *3: Under engine braking, downshifting to 1st or 2nd gear is prohibited.
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