Fail-Safe Chart

FAIL-SAFE CHART

1. FAIL-SAFE CHART
This function minimizes the loss of the ECT functions when any malfunction occurs in a sensor or solenoid.
a) Vehicle speed signal (SPD):
When there are problems with vehicle speed signals, O/D up-shift is prohibited.
b) Speed sensor (NT):
When the input turbine speed sensor has a malfunction, O/D up-shift is prohibited.
c) Automatic Transmission Fluid (ATF) temperature sensor:
When the ATF temperature sensor has a malfunction, O/D up-shift 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, O/D up-shift is prohibited.
f) Engine Coolant Temperature (ECT) sensor:
When the ECT sensor has a malfunction, O/D upshift is prohibited.
g) Knock sensor:
When the knock sensor has a malfunction, O/D upshift is prohibited.
h) Throttle position sensor:
When the throttle position sensor has a malfunction, O/D up-shift is prohibited.
i) Shift solenoid valve S1 and S2:
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.
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 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.