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.
Electronic Ignition System Diagnosis (3.4L): Description
Ignition Control (IC) module has independent power and ground circuits. Circuits between IC module and Powertrain Control Module (PCM) consist of the following circuits:
- IC timing signal.
- IC timing control.
- Low-resolution engine speed signal.
- Low reference signal.
IC module sends 3x signals to PCM. IC module controls timing advance during engine cranking. Timing advance changes to PCM control after the following actions:
- PCM receives the second 3x signal.
- PCM applies 5 volts to IC timing signal circuit.
- Timing advance switches to PCM control.
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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.