Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
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.
| DTCs | Components | Fail-Safe Operations | Fail-Safe Deactivation Conditions |
|---|---|---|---|
| P0031, P0032, P0051, P0052, P101D and P103D | Air Fuel Ratio (A/F) Sensor Heater | ECM turns off A/F sensor heater. | Ignition switch off |
| P0037, P0038, P0057, P0058, P102D and P105D | Heated Oxygen (HO2) Sensor Heater | ECM turns off HO2 sensor heater. | Ignition switch off |
| P0102 and P0103 | Mass Air Flow (MAF) Meter | ECM calculates ignition timing according to engine speed and throttle valve position. | Pass condition detected |
| 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, P060A, P060B, P060D, P060E, P0657, P1607, P2102, P2103, P2111, P2112, P2118, P2119 and P2135 | Electronic Throttle Control System (ETCS) | ECM cuts off throttle actuator current and throttle valve returned to 7° 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 |
| P0300, P0301, P0302, P0303, P0304, P0305 and P0306*2 |
|
When catalyst damage misfire occurs (MIL blinking), following fail-safe operation performed for catalyst overheat malfunction prevention
|
Pass condition detected and then ignition switch turned off |
| P0327, P0328, P0332 and P0333 | Knock Sensor | ECM sets ignition timing to maximum retard. | Ignition switch off |
| P0351 to P0356 | 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 circuit malfunctions, ECM controls engine using other circuit. If both 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 |
HINT:
*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.
*2: Misfire related fail-safe operations occur when catalyst overheat malfunctions occur.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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