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Fail-Safe Chart

  1. FAIL-SAFE 

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

    1. ATF (Automatic Transmission Fluid) temperature sensor:

      When the ATF temperature sensor has a malfunction, 5th upshift is prohibited.

    2. Counter gear speed sensor NC (Speed sensor NC): When the counter gear speed sensor has a malfunction, 5th upshift is prohibited.
    3. Shift solenoid valve DSL:

      When the solenoid valve DSL has a malfunction, the current to the solenoid valve is stopped.

      This stops lock-up control, then fuel economy decreases.

    4. Shift solenoid valve SL1, SL2, SL3 and S4:

      Fail safe function:

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

      Manual shifting as shown in the following table must be done (In case of a short circuit, the ECM stops sending the current to the short circuited solenoid).

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

      HINT:

      FL: Flex Lock-up

SOLENOID VALVE SPECIFICATION

Normal Solenoid Valve SL1 ON OFF ON OFF OFF
SL2 ON ON OFF FL FL
SL3 OFF OFF OFF ON ON
S4 OFF OFF OFF OFF ON
Gear Position 1st 2nd 3rd 4th 5th
SL1 Malfunction (During driving at 1st or 2nd) Solenoid Valve SL1 OFF
SL2 ON ON OFF to ON FL to ON FL to ON
SL3 OFF OFF OFF ON to OFF ON to OFF
S4 OFF OFF OFF OFF ON to OFF
Gear Position 1st to 2nd 2nd 3rd to 2nd 4th to 2nd 5th to 2nd
SL1 Malfunction (During driving at 3rd) Solenoid Valve SL1 OFF
SL2 ON to FL ON to FL OFF to FL FL FL
SL3 OFF OFF OFF ON to FL ON to FL
S4 OFF to ON OFF to ON OFF to ON OFF to ON ON
Gear Position 1st to 4th 2nd to 4th 3rd to 4th 4th 5th to 4th
SL1 Malfunction (During driving at 4th or 5th) Solenoid Valve SL1 OFF
SL2 ON to FL ON to FL OFF to FL FL FL
SL3 OFF to ON OFF to ON OFF to ON ON ON
S4 OFF OFF OFF OFF ON
Gear Position 1st to 4th 2nd to 4th 3rd to 4th 4th 5th to 4th
SL2 Malfunction Solenoid Valve SL1 ON OFF to ON ON OFF to ON OFF to ON
SL2 OFF
SL3 OFF OFF OFF ON to OFF ON to OFF
S4 OFF to ON OFF to ON OFF to ON OFF to ON ON
Gear Position 1st to 4th 2nd to 4th 3rd to 4th 4th 5th to 4th
SL3 Malfunction Solenoid Valve SL1 ON OFF ON OFF to ON OFF to ON
SL2 ON ON OFF FL FL
SL3 OFF
S4 OFF OFF OFF OFF to ON ON
Gear Position 1st 2nd 3rd 4th 5th to 4th
S4 Malfunction Solenoid Valve SL1 ON OFF ON OFF OFF
SL2 ON ON OFF FL FL
SL3 OFF OFF OFF ON ON
S4 OFF
Gear Position 1st 2nd 3rd 4th 5th to 4th
SL1, SL2, SL3, and S4 Malfunction Solenoid Valve SL1 OFF
SL2 OFF
SL3 OFF
S4 OFF
Gear Position 1st to 4th 2nd to 4th 3rd to 4th 4th 5th to 4th