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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 a sensor or solenoid.

    FAIL-SAFE CHART

    Malfunction Part Function
    No 1 ATF Temperature Sensor During a No 1 ATF temperature sensor malfunction, up-shift to the 5th gear and flex lock-up clutch control are prohibited
    Output Speed Sensor (SP2) During an output speed sensor malfunction, shift control is effected through the input speed sensor signal (NT)
    Shift Solenoid Valve S1, S2 and SR The current to the malfunctioning solenoid valve is cut off and control is performed by operating the other normal solenoid valves
    Shift control is effected depending on the failed solenoid as described in the table below.
    Shift Solenoid Valve SL1 and SL2 During a solenoid valve SL1 or SL2 malfunction, up-shift to the 5th gear is prohibited
    Shift Solenoid Valve SLT During a solenoid valve SLT malfunction, the current to the solenoid valve is stopped This stops optimal line pressure control, and shift shock increases However, shifting is effected through normal clutch pressure control
    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, and fuel economy decreases

    Fail-safe function:

    If any of the shift solenoid valve circuits has an open or short failure, the ECM turns the other shift solenoids ON and OFF in order to shift into the gear positions shown in the table below.

    In case of a short circuit, the ECM stops sending current to the short-circuited solenoid.

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

    HINT:

    • Electrical malfunction: Condition is shown above the "↓".
    • Fail-safe mode. Condition is shown below the "↓".
    • E/B: Engine brake.
      SHIFT SOLENOID MALFUNCTION CHART

      Position Normal Shift Solenoid S1 Malfunction
      Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
      R R ON OFF OFF OFF ON R X OFF OFF OFF ON
      D 1st ON OFF OFF OFF ON 4th ↓ 3rd X OFF ↓ ON OFF OFF ON
      2nd ON ON OFF OFF ON 3rd X ON OFF OFF ON
      3rd OFF ON OFF OFF ON 3rd X ON OFF OFF ON
      4th OFF OFF OFF OFF ON 4th X OFF OFF OFF ON
      5th OFF OFF ON ON OFF 5th X OFF ON ON OFF
      4 1st ON OFF OFF OFF ON 4th ↓ 3rd X OFF ↓ ON OFF OFF ON
      2nd ON ON OFF OFF ON 3rd X ON OFF OFF ON
      3rd OFF ON OFF OFF ON 3rd X ON OFF OFF ON
      4th OFF OFF OFF OFF ON 4th X OFF OFF OFF ON
      3 1st ON OFF OFF OFF ON 3rd ↓ 3rd E/B X OFF ↓ ON OFF OFF ON ↓ OFF
      2nd ON ON OFF OFF ON 3rd ↓ 3rd E/B X ON OFF OFF ON ↓ OFF
      3rd E/B OFF ON OFF OFF OFF 3rd E/B X ON OFF OFF OFF
      2 1st ON OFF OFF OFF ON 1st X OFF OFF OFF ON
      2nd E/B ON ON ON OFF OFF 3rd E/B X ON ON OFF OFF
      L 1st E/B ON OFF OFF OFF OFF 1st E/B X OFF OFF OFF OFF
      HINT:
      X: Malfunction
    SHIFT SOLENOID MALFUNCTION CHART

    Position Shift Solenoid S2 Malfunction Shift Solenoid SR Malfunction
    Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
    R R ON X OFF OFF ON R ON OFF X OFF ON
    D 1st ON X OFF OFF ON 1st ON OFF X OFF ON
    1st ↓ 4th ON ↓ OFF X OFF OFF ON 2nd ON ON X OFF ON
    4th OFF X OFF OFF ON 3rd OFF ON X OFF ON
    4th OFF X OFF OFF ON 4th OFF OFF X OFF ON
    5th OFF X ON ON OFF 4th OFF OFF X ON OFF
    4 1st ON X OFF OFF ON 1st ON OFF X OFF ON
    1st ↓ 4th ON ↓ OFF X OFF OFF ON 2nd ON ON X OFF ON
    4th OFF X OFF OFF ON 3rd OFF ON X OFF ON
    4th OFF X OFF OFF ON 4th OFF OFF X OFF ON
    3 1st ON X OFF OFF ON 1st ON OFF X OFF ON
    1st ↓ 3rd E/B ON ↓ OFF X OFF OFF ON ↓ OFF 2nd ON ON X OFF ON
    3rd E/B OFF X OFF OFF OFF 3rd E/B ↓ 3rd OFF ON X OFF OFF ↓ ON
    2 1st ON X OFF OFF ON 1st ON OFF X OFF ON
    2nd E/B ↓ 4th ON ↓ OFF X ON OFF OFF ↓ ON 2nd ON ON X OFF OFF
    L 1st E/B ON X OFF OFF OFF 1st E/B ON OFF X OFF OFF
    HINT:
    X: Malfunction
    SHIFT SOLENOID MALFUNCTION CHART

    Position Shift Solenoid S1 and S2 Malfunction Shift Solenoid S1 and SR Malfunction
    Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
    R R X X OFF OFF ON R X OFF X OFF ON
    D 4th X X OFF OFF ON 4th ↓ 3rd X OFF ↓ ON X OFF ON
    4th X X OFF OFF ON 3rd X ON X OFF ON
    4th X X OFF OFF ON 3rd X ON X OFF ON
    4th X X OFF OFF ON 4th X OFF X OFF ON
    5th X X ON ON OFF 4th X OFF X ON ↓ OFF OFF ↓ ON
    4 4th X X OFF OFF ON 4th ↓ 3rd X OFF ↓ ON X OFF ON
    4th X X OFF OFF ON 3rd X ON X OFF ON
    4th X X OFF OFF ON 3rd X ON X OFF ON
    4th X X OFF OFF ON 4th X OFF X OFF ON
    3 3rd ↓ 3rd E/B X X OFF OFF ON ↓ OFF 3rd X OFF ↓ ON X OFF ON
    3rd ↓ 3rd E/B X X OFF OFF ON ↓ OFF 3rd X ON X OFF ON
    3rd E/B X X OFF OFF OFF 3rd E/B ↓ 3rd X ON X OFF OFF ↓ ON
    2 1st X X OFF OFF ON 1st X OFF X OFF ON
    4th X X ON OFF OFF ↓ ON 2nd X ON X OFF OFF
    L 1st E/B X X OFF OFF OFF 1st E/B X OFF X OFF OFF
    SHIFT SOLENOID MALFUNCTION CHART

    Position Shift Solenoid S2 and SR Malfunction Shift Solenoid S1, S2 and SR Malfunction
    Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
    R R ON X X OFF ON R X X X OFF ON
    D 1st ON X X OFF ON 4th X X X OFF ON
    1st ↓ 4th ON ↓ OFF X X OFF ON 4th X X X OFF ON
    4th OFF X X OFF ON 4th X X X OFF ON
    4th OFF X X OFF ON 4th X X X OFF ON
    4th OFF X X ON ↓ OFF OFF ↓ ON 4th X X X ON ↓ OFF OFF ↓ ON
    4 1st ON X X OFF ON 4th X X X OFF ON
    1st ↓ 4th ON ↓ OFF X X OFF ON 4th X X X OFF ON
    4th OFF X X OFF ON 4th X X X OFF ON
    4th OFF X X OFF ON 4th X X X OFF ON
    3 1st ON X X OFF ON 3rd X X X OFF ON
    1st ↓ 3rd ON ↓ OFF X X OFF ON 3rd X X X OFF ON
    3rd E/B ↓ 3rd OFF X X OFF OFF ↓ ON 3rd E/B ↓ 3rd X X X OFF OFF ↓ ON
    2 1st ON X X OFF ON 1st X X X OFF ON
    1st E/B ↓ 1st ON X X OFF OFF ↓ ON 1st E/B ↓ 1st X X X OFF OFF ↓ ON
    L 1st E/B ON X X OFF OFF 1st E/B X X X OFF OFF
    HINT:
    X: Malfunction