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.
Circuit Description
The Ignition Control Module (ICM) has independent power and ground circuits. The circuits between the ICM and the Powertrain Control Module (PCM) consist of the following circuits:
- The IC timing signal.
- The IC timing control.
- The low-resolution engine speed signal.
- A low reference signal.
The ICM sends 3X signals to the PCM. The ICM controls the timing advance during engine cranking. The timing advance changes to PCM control after the following actions:
- The PCM receives the second 3X signal.
- The PCM applies 5 volts to the IC timing signal circuit.
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.