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Fail-Safe Chart

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

DTC Component Fail-Safe Operation Fail-Safe Deactivation Condition
P0031, P0032, P0051, P0052, P101D and P103D Air Fuel Ratio Sensor Heater ECM turns off the air fuel ratio sensor heater. Ignition switch off
P0037, P0038, P0057, P0058, P102D and P105D Heated Oxygen Sensor Heater ECM turns off the heated oxygen sensor heater. Ignition switch off
P0102 and P0103 Mass Air Flow Meter ECM calculates the ignition timing according to the engine speed and throttle valve position. Pass condition detected
P0112 and P0113 Intake Air Temperature Sensor ECM estimates the intake air temperature to be 20°C (68°F). Pass condition detected
P0115, P0117 and P0118 Engine Coolant Temperature Sensor ECM estimates the engine coolant temperature to be 80°C (176°F). Pass condition detected
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0604, P0606, P060A, P060B, P060D, P060E, P0657, P2102, P2103, P2111, P2112, P2118, P2119 and P2135 Electronic Throttle Control System (ETCS) ECM cuts off the throttle actuator current and the throttle valve returns to a throttle position of 7° by the return spring.
The ECM then adjusts the engine output by controlling the fuel injection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal position to allow the vehicle to continue at minimal speed.*1
Pass condition detected and then ignition switch turned off
P0300, P0301, P0302, P0303, P0304, P0305 and P0306*2
  • Fuel Injector
  • Electronic Throttle Control System
When a misfire occurs, fuel cut is performed for catalyst overheat malfunction prevention.
  • During normal load and normal engine speed (MIL is blinking):

    - Fuel cut is performed on the malfunctioning cylinder.

  • During high load and high engine speed (MIL is blinking):

    - Throttle valve opening angle control is performed.

    - All cylinder fuel cut or malfunctioning cylinder fuel cut is performed.

Pass condition detected and then ignition switch turned off
P0327, P0328, P0332 and P0333 Knock Sensor ECM sets the ignition timing to maximum retard. Ignition switch off
P0351 to P0356 Igniter ECM cuts the fuel. Pass condition detected
P2120, P2121, P2122, P2123, P2125, P2127, P2128 and P2138 Accelerator Pedal Position Sensor Accelerator pedal position sensor has 2 sensor circuits: Main and Sub.
If either circuit malfunctions, the ECM controls the engine using the other circuit.
If both circuits malfunction, the ECM regards the accelerator pedal as being released. As a result, the throttle valve closes and the engine idles.
Pass condition detected and then ignition switch turned off

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