Camshaft Position Sensor
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The Camshaft Position (CMP) sensor signal is a digital ON/OFF pulse, output once per revolution of the camshaft. The CMP sensor does not directly affect the operation of the ignition system. The CMP sensor information is used by the Powertrain Control Module (PCM) to determine the position of the valve train relative to the CKP. By monitoring the CMP and CKP signals the PCM can accurately time the operation of the fuel injectors. The CMP sensor shares 12-volt and low reference circuits with the CKP sensor. The CMP signal circuit is input to the ICM. CMP sensor is located in the engine block below the water pump, above the crankshaft pulley. See Fig 1.