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.
Crankshaft Position Sensor
FUNCTIONS WITHIN THE SYSTEM
The ECM judges the engine speed based on the crankshaft position signal that is input into it. It also includes a reverse rotation detection function, and if it detects reverse engine rotation while idling stop is activated, it performs early start control when the engine restarts.
INDIVIDUAL FUNCTION WITHIN THE SYSTEM
The ECM inputs the voltage change caused by the change in magnetic field generated close to the crankshaft position sensor as signal voltage.
INDIVIDUAL OPERATION
Crankshaft position sensor consists of a permanent magnet and Hall IC. When the engine is running, the high and low parts of the teeth cause the gap with the sensor to change. The changing gap causes the magnetic field near the sensor to change. Due to the changing magnetic field, the voltage from the sensor changes.
COMPONENT LOCATION
Crankshaft position sensor (POS) is installed on the cylinder block rear end.
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.