Sensor, Crankshaft Position: Operation
WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Crankshaft Position (CKP) sensor contains a hall effect device. A rotating, notched target wheel (tone wheel) for the CKP is located behind the engine harmonic balancer (2). This hall effect device detects notches located on the tone wheel. As the tone wheel rotates, the notches pass the tip of the CKP.
- When the leading edge of the tone wheel notch passes the tip of the CKP, the following occurs: The interruption of magnetic field causes the voltage to switch high resulting in a signal of approximately 5 volts.
- When the trailing edge of the tone wheel notch passes the tip of the CKP, the following occurs: The change of the magnetic field causes the signal voltage to switch low to 0 volts.
- The Camshaft Position Sensor (CMP) also provides a signal to the Powertrain Control Module (PCM) at all times when the engine is running. The PCM uses this CMP information primarily on engine start-up. Once the engine is running, the PCM uses the CMP as a backup sensor for engine speed.