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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.

    SYMBOLS TERMINAL DESCRIPTION SPECIFIED CONDITION CHART

    Malfunction Part Function
    DTC P0710, P0712 and P0713: 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.
    DTC P0722: Output Speed Sensor (SP2) During an output speed sensor malfunction, shift control is effected through the input speed sensor signal (NT).
    DTC P0751, P0756, P0771, P0973, P0974, P0976, P0977, P0985 and P0986: Shift Solenoid Valve S1, S2 and SR The current to the failed solenoid valve is cut off and control is effected by operating the other solenoid valves with normal operation. Shift control is effected depending on the failed solenoid as described in the table below.
    DTC P0748, P0776 and P0778: Shift Solenoid Valve SL1 and SL2 During a solenoid valve SL1 or SL2 malfunction, up-shift to the 5th gear is prohibited.
    DTC P02714 and 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, and shift shock increases. However, shifting is effected through normal clutch pressure control.
    DTC P2757: 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 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 a short circuit, the ECM stops sending current to the 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

Position NORMAL S1 OFF
Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
"R" R ON OFF OFF OFF ON R OFF OFF OFF OFF ON
"D" 1st ON OFF OFF OFF ON 4th --> 3rd OFF OFF --> ON OFF OFF ON
2nd ON ON OFF OFF ON 3rd OFF ON OFF OFF ON
3rd OFF ON OFF OFF ON 3rd OFF ON OFF OFF ON
4th OFF OFF OFF OFF ON 4th OFF OFF OFF OFF ON
5th OFF OFF ON ON OFF 5th OFF OFF ON ON OFF
"3" 1st ON OFF OFF OFF ON 3rd --> 3rd E/B OFF OFF --> ON OFF OFF ON --> OFF
2nd ON ON OFF OFF ON 3rd --> 3rd E/B OFF ON OFF OFF ON --> OFF
3rd E/B OFF ON OFF OFF OFF 3rd E/B OFF ON OFF OFF OFF
4th OFF OFF ON OFF ON 4th OFF OFF ON OFF ON
5th OFF OFF ON ON OFF 5th OFF OFF ON ON OFF
"2" 1st ON OFF OFF OFF ON 1st OFF OFF OFF OFF ON
2nd E/B ON ON ON OFF OFF 3rd E/B OFF ON ON OFF OFF
3rd E/B OFF ON ON OFF OFF 3rd E/B OFF ON ON OFF OFF
4th OFF OFF ON OFF ON 4th OFF OFF ON OFF ON
5th OFF OFF ON ON OFF 5th OFF OFF ON ON OFF
"L" 1st E/B ON OFF OFF OFF OFF 1st E/B OFF OFF OFF OFF OFF
2nd E/B ON ON ON OFF OFF 3rd E/B OFF ON ON OFF OFF
3rd E/B OFF ON ON OFF OFF 3rd E/B OFF ON ON OFF OFF
4th OFF OFF ON OFF ON 4th OFF OFF ON OFF ON
5th OFF OFF ON ON OFF 5th OFF OFF ON ON OFF
FAIL-SAFE CHART FOR ELECTRICAL MALFUNCTION

Position S2 OFF SR OFF
Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
"R" R ON OFF OFF OFF ON R ON OFF OFF OFF ON
"D" 1st ON OFF OFF OFF ON 1st ON OFF OFF OFF ON
1st --> 4th ON --> OFF FF OFF OFF ON 2nd ON ON OFF OFF ON
4th OFF OFF OFF OFF ON 3rd OFF ON OFF OFF ON
4th OFF OFF OFF OFF ON 4th OFF OFF OFF OFF ON
5th OFF OFF ON N OFF 4th OFF OFF OFF ON OFF
"3" 1st ON OFF OFF FF ON 1st ON OFF OFF OFF ON
1st --> 3rd E/B ON --> OFF OFF OFF OFF ON --> OFF 2nd ON ON OFF OFF ON
3rd E/B OFF OFF OFF OFF OFF 3rd E/B --> 3rd OFF ON OFF OFF OFF --> ON
4th OFF OFF ON OFF ON 3rd OFF OFF --> ON OFF OFF ON --> ON
5th OFF OFF ON ON OFF 3rd E/B --> 3rd OFF OFF --> ON OFF ON --> OFF OFF --> ON
"2" 1st ON OFF OFF OFF ON 1st ON OFF OFF OFF ON
2nd E/B --> 4th ON --> OFF OFF ON OFF OFF --> ON 2nd ON ON OFF OFF OFF
Fail 4th OFF OFF ON OFF OFF --> ON 2nd OFF --> ON ON OFF OFF OFF
4th OFF OFF ON OFF ON 1st --> 2nd OFF --> ON OFF --> ON OFF OFF ON --> OFF
5th OFF OFF ON ON OFF 1st E/B --> 2nd OFF --> ON ON OFF ON --> OFF OFF
"L" 1st E/B ON OFF OFF OFF OFF 1st E/B ON OFF OFF OFF OFF
2nd E/B --> 4th ON --> OFF OFF ON OFF OFF --> ON 2nd ON ON OFF OFF OFF
Fail 4th OFF OFF ON OFF OFF --> ON 2nd OFF --> ON ON OFF OFF OFF
4th OFF OFF ON OFF ON 1st --> 2nd OFF --> ON OFF --> ON OFF OFF ON --> OFF
5th OFF OFF ON ON OFF 1st E/B --> 2nd OFF --> ON OFF --> ON OFF ON --> OFF OFF
FAIL-SAFE CHART FOR ELECTRICAL MALFUNCTION

Position S1 S2 OFF S2 SR OFF
Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
"R" R OFF OFF OFF OFF ON R ON OFF OFF OFF ON
"D" 4th OFF OFF OFF OFF ON 1st ON OFF OFF OFF ON
4th OFF OFF OFF OFF ON 1st --> 4th ON --> OFF OFF OFF OFF ON
4th OFF OFF OFF OFF ON 4th OFF OFF OFF OFF ON
4th OFF OFF OFF OFF ON 4th OFF OFF OFF OFF ON
5th OFF OFF ON ON OFF 4th OFF OFF OFF ON --> OFF OFF --> ON
"3" 3rd --> 3rd E/B OFF OFF OFF OFF ON --> OFF 1st ON OFF OFF OFF ON
3rd --> 3rd E/B OFF OFF OFF OFF ON --> OFF 1st E/B --> 3rd ON --> OFF OFF OFF OFF ON --> ON
3rd E/B OFF OFF OFF OFF OFF 3rd E/B --> 3rd OFF OFF OFF OFF OFF --> ON
4th OFF OFF ON OFF ON 3rd OFF OFF OFF OFF ON --> ON
5th OFF OFF ON ON OFF 1st E/B --> 3rd OFF OFF OFF ON --> OFF OFF --> ON
"2" 1st OFF OFF OFF OFF ON 1st ON OFF OFF OFF ON
Fail 4th OFF OFF ON OFF OFF --> ON 1st E/B --> 1st ON OFF OFF OFF OFF --> ON
Fail 4th OFF OFF ON OFF OFF --> ON 1st E/B --> 1st OFF --> ON OFF OFF OFF OFF --> ON
4th OFF OFF ON OFF ON 1st OFF --> ON OFF OFF OFF ON
5th OFF OFF ON ON OFF 1st E/B --> 1st OFF --> ON OFF OFF ON --> OFF OFF --> ON
"L" 1st E/B OFF OFF OFF OFF OFF 1st E/B ON OFF OFF OFF OFF
Fail 4th OFF OFF ON OFF OFF --> ON 1st E/B --> 1st ON OFF OFF OFF OFF --> ON
Fail 4th OFF OFF ON OFF OFF --> ON 1st E/B --> 1st OFF --> ON OFF OFF OFF OFF --> ON
4th OFF OFF ON OFF ON 1st OFF --> ON OFF OFF OFF ON
5th OFF OFF ON ON OFF 1st E/B --> 1st OFF --> ON OFF OFF ON --> OFF OFF --> ON
FAIL-SAFE CHART FOR ELECTRICAL MALFUNCTION

Position S1 S2 OFF S2 SR OFF
Gear S1 S2 SR SL1 SL2 Gear S1 S2 SR SL1 SL2
"R" R OFF OFF OFF OFF ON R OFF OFF OFF OFF ON
"D" 4th --> 3rd OFF OFF --> ON OFF OFF ON 4th OFF OFF OFF OFF O
3rd OFF ON OFF OFF ON 4th OFF OFF OFF OFF ON
3rd OFF ON OFF OFF ON 4th OFF OFF OFF OFF ON
4th OFF OFF OFF OFF ON 4th OFF OFF OFF OFF ON
4th OFF OFF OFF ON --> OFF OFF --> ON 4th OFF OFF OFF ON --> OFF OFF --> ON
"3" 3rd OFF OFF --> ON OFF OFF ON --> ON 3rd OFF OFF OFF OFF ON --> ON
3rd OFF ON OFF OFF ON --> ON 3rd OFF OFF OFF OFF ON --> ON
3rd E/B --> 3rd OFF ON OFF OFF OFF --> ON 3rd E/B --> 3rd OFF OFF OFF OFF OFF --> ON
3rd OFF OFF --> ON OFF OFF ON --> ON 3rd OFF OFF OFF OFF ON --> ON
3rd E/B --> 3rd OFF OFF --> ON OFF ON --> OFF OFF --> ON 3rd E/B --> 3rd OFF OFF OFF ON --> OFF OFF --> ON
"2" 1st OFF OFF OFF OFF ON 1st OFF OFF OFF OFF O
2nd OFF ON OFF OFF OFF 1st E/B --> 1st OFF OFF OFF OFF OFF --> ON
2nd OFF ON OFF OFF OFF 1st E/B --> 1st OFF OFF OFF OFF OFF --> ON
1st --> 2nd OFF OFF --> ON OFF OFF ON --> OFF 1st OFF OFF OFF OFF ON
1st E/B --> 2nd OFF OFF --> ON OFF ON --> OFF OFF 1st E/B --> 1st OFF OFF OFF ON --> OFF OFF --> ON
"L" 1st E/B OFF OFF OFF OFF OFF 1st E/B OFF OFF OFF OFF OFF
2nd OFF ON OFF OFF OFF 1st E/B --> 1st OFF OFF OFF OFF OFF --> ON
2nd OFF ON OFF OFF OFF 1st E/B --> 1st OFF OFF OFF OFF OFF --> ON
1st --> 2nd OFF OFF --> ON OFF OFF ON --> OFF 1st OFF OFF OFF OFF ON
1st E/B --> 2nd OFF OFF --> ON OFF ON --> OFF OFF 1st E/B --> 1st OFF OFF OFF ON --> OFF OFF --> ON

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