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, 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 accordance with engine RPM 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, P0122 and P0123 | Throttle Position (TP) Sensor | ECM cuts fuel intermittently. | Pass condition detected and ignition switch OFF |
| P0121 | TP Sensor | ECM cuts fuel intermittently. | Pass condition detected and ignition switch OFF |
| P0325 | Knock Sensor | ECM sets ignition timing to maximum retard. | Ignition switch OFF |
| P0351 to P0354 | Igniter | ECM cuts fuel. | Pass condition detected |
Use the Manual With the Right Hardware
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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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