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 (POS) | Engine speed* 4 | Fuel injection & mixture ratio control | Fuel injector | |
| Camshaft position sensor (PHASE) | Camshaft position | |||
| Mass air flow sensor | Amount of intake air | |||
| Intake air temperature sensor 1 | Intake air temperature | |||
| Engine coolant temperature sensor | Engine coolant temperature | |||
| Air fuel ratio (A/F) sensor 1 | Density of oxygen in exhaust gas | |||
| Fuel rail pressure sensor | Fuel rail pressure | |||
| Throttle position sensor | Throttle position | |||
| Accelerator pedal position sensor | Accelerator pedal position | |||
| Battery | Battery voltage* 4 | |||
| Knock sensor | Engine knocking condition | |||
| Heated oxygen sensor 2* 1 | Density of oxygen in exhaust gas | |||
| Transmission range switch* 2 | Gear position | |||
| Park/neutral position (PNP) switch* 3 | ||||
| G sensor | Inclination angle | |||
| Turbocharger boost sensor | Turbocharger boost | |||
| ABS actuator and electric unit (control unit) | CAN communication |
|
||
| BCM | CAN communication | A/C ON signal | ||
| Combination meter | CAN communication | Vehicle speed signal | ||
* 1: This sensor is not used to control the engine system under normal conditions.
* 2: CVT models
* 3: M/T models
* 4: ECM determines the start signal status by the signals of engine speed and battery voltage.
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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