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Camshaft Position Sensor: Description and Operation






DESCRIPTION
The Camshaft Position Sensor (CMP) is located on the timing cover behind the water pump near the camshaft sprocket. As the camshaft sprocket turns, a magnet in it activates the Hall effect switch in the camshaft position sensor. When the Hall-effect switch is activated, it grounds the signal line to the Ignition Control Module (ICM), pulling the camshaft position sensor signal circuit's applied voltage low. This is interpreted as a CMP Sensor signal. The CMP Sensor signal is created as piston #1 is approximately 25 degrees after top dead center on the power stroke.