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.
Mode I
This is normal operating mode. In this mode, the CHECK ENGINE light and Red Light Emitting Diode (LED) inspection light in ECU stay on when the ignition is turned on, engine off (bulb check). If the engine is started, CHECK ENGINE light and Red LED in ECU should turn off, unless a fault or trouble code is present (Calif. models) or if the ECU or crank angle sensor is malfunctioning (Calif. and Fed. models).
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.