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Fail-Safe Chart

When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL illuminates.

FAIL-SAFE CHART

DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103
Mass air flow sensor circuit Engine speed will not rise more than 2, 400 RPM due to the fuel cut.
P0117
P0118
Engine coolant temperature sensor circuit Engine coolant temperature will be determined by ECM based on the following conditions. CONSULT-III displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided (CONSULT-III display)
Just as ignition switch is turned ON or START 40°C (104°F)
Approx. 4 minutes or more after engine starting. 80°C (176°F)
Except as shown above 40 - 80°C (104 - 176°F) (Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135
Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
P0643 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2100
P2103
Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2101 Electric throttle control function ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2118 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2119 Electric throttle control actuator (When electric throttle control actuator does not function properly due to the return spring malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the idle position. The engine speed will not rise more than 2, 000 RPM.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20 degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is being driven, it slows down gradually because of fuel cut. After the vehicle stops, the engine stalls.
The engine can restart in the N or P position, and engine speed will not exceed 1, 000 RPM or more.
P2122
P2123
P2127
P2128
P2138
Accelerator pedal position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.

Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means of operating the fail-safe function.

The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the driver to repair the malfunction.

FAIL-SAFE CHART

Engine operating condition in fail-safe mode Engine speed will not rise more than 2, 500 RPM due to the fuel cut