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Fail-Safe Chart

If any of the following DTCs are set, the ECM enters fail-safe mode to allow the vehicle to be driven temporarily.

FAIL-SAFE CHART

DTCs Components Fail-Safe Operations Fail-Safe Deactivation Conditions
P0031 and P0032 Air-Fuel Ratio (A/F) Sensor Heater ECM turns off A/F sensor heater. Ignition switch OFF
P0037 and P0038 Heated Oxygen (HO2) Sensor Heater ECM turns off HO2 sensor heater. Ignition switch OFF
P0100, P0102 and P0103 Mass Air Flow (MAF) Meter ECM calculates ignition timing according to engine speed and throttle valve position. Pass condition detected
P0110, P0112 and P0113 Intake Air Temperature (IAT) Sensor ECM estimates IAT to be 20°C (68°F). Pass condition detected
P0115, P0117 and P0118 Engine Coolant Temperature (ECT) Sensor ECM estimates ECT to be 80°C (176°F). Pass condition detected
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0604, P0606, P0607, P0657, P2102, P2103, P2111, P2112, P2118, P2119 and P2135 Electronic Throttle Control System (ETCS) ECM cuts off throttle actuator current and throttle valve returned to 6.5° throttle position by return spring.
ECM then adjusts engine output by controlling fuel injection (intermittent fuel-cut) and ignition timing in accordance with accelerator pedal opening angle, to allow vehicle to continue at minimal speed.(1)
Pass condition detected and then ignition switch turned OFF
P0325, P0327 and P0328 Knock Sensor ECM sets ignition timing to maximum retard. Ignition switch OFF
P0351 to P0354 Igniter ECM cuts fuel. Pass condition detected
P2120, P2121, P2122, P2123, P2125, P2127, P2128 and P2138 Accelerator Pedal Position (APP) Sensor APP sensor has 2 sensor circuits: Main and Sub.
If either of circuits malfunctions, ECM controls engine using other circuit.
If both of circuits malfunction, ECM regards accelerator pedal as being released. As a result, throttle valve is closed and engine idles.
Pass condition detected and then ignition switch turned OFF
NOTE:
(1) The vehicle can be driven slowly when the accelerator pedal is depressed firmly and slowly. If the accelerator pedal is depressed quickly, the vehicle may speed up and slow down erratically.