Fail Safe Chart

FAIL-SAFE CHART

1. FAIL-SAFE
This function minimizes the loss of the ECT functions when any malfunction occurs in each sensor or solenoid.

a. Vehicle speed signal (SPD):
When there are problems with vehicle speed signals, 4th upshift is prohibited.
b. Input turbine speed sensor NT (Speed sensor NT):
When the Input turbine speed sensor has a malfunction, 4th upshift is prohibited.
c. ATF (Automatic Transmission Fluid) temperature sensor:
When the ATF temperature sensor has a malfunction, 4th upshift is prohibited.
d. Shift solenoid valve SL:
If the ECM detects a malfunction in the solenoid valve SL, it turns the valve off.
e. Shift solenoid valve SLT:
When the solenoid valve SLT has a malfunction, 4th upshift is prohibited.
f. Engine coolant temperature sensor:
When the engine coolant temperature sensor has a malfunction, 4th upshift is prohibited.
g. Knock sensor:
When the knock sensor has a malfunction, 4th upshift is prohibited.
h. Throttle position sensor:
When the throttle position sensor has a malfunction, 4th upshift is prohibited.
i. Shift solenoid valve S1 and S2:

Fail-Safe Chart:

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 given. The ECM also turns the shift solenoid valve ST OFF at the same time. If both solenoids malfunction, hydraulic control cannot be performed electronically and must be done manually. 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 circuit solenoid).
Even if starting the engine in the fail-safe mode, the gear position remain in the same position.