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.
Malfunction Warning Mode
Description
In this function ECM turns on or blinks MIL when it detects a malfunction in the emission control system components and/or the powertrain control components (which affect vehicle emissions) to inform the driver that a malfunction has been detected.
Operation Procedure
- Turn ignition switch ON.
- Check that MIL illuminates.
If it remains OFF, check MIL circuit. Refer to Diagnosis Procedure .
- Start engine and let it idle.
- For two trip detection logic diagnoses, ECM turns on MIL when it detects the same malfunction twice in the two consecutive driving cycles.
- For 1st trip detection logic diagnoses, ECM turns on MIL when it detects a malfunction in one driving cycle.
- ECM blinks MIL when it detects a malfunction that may damage the three way catalyst (misfire).
NO RELATED
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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.