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.
Input/Output Signal Chart
| Sensor | Input signal to ECM | ECM function | Actuator |
|---|---|---|---|
| Crankshaft position sensor | Engine speed * 1 | Cooling fan speed request signal * 2 | IPDM E/R ↓ Electrically-controlled cooling fan coupling |
| Camshaft position sensor | Camshaft position | ||
| Engine coolant temperature sensor | Engine coolant temperature | ||
| Refrigerant pressure sensor | Refrigerant pressure | ||
| Intake air temperature sensor | Intake air temperature | ||
| Battery | Battery voltage | ||
| Combination meter | Vehicle speed signal * 2 | ||
| BCM | A/C switch signal * 2 | ||
| Cooling fan speed sensor | Cooling fan speed |
*1: The ECM determines the engine speed by the signals of crankshaft position and camshaft position.
*2: This signal is sent to ECM via the CAN communication line.
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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