DTC P0340: Camshaft Position Sensor (Phase): Description
WARNING: This page is about a different car, the 2002 Nissan Pathfinder and 2002 Infiniti QX4. However, it is still accessible from the selected car via links, so may be relevant.
The Camshaft Position (CMP) sensor (PHASE) located on front engine cover facing the camshaft sprocket. CMP sensor (PHASE) is used to detect cylinder number signal.
The sensor consists of a permanent magnet, core and coil. When engine is running, gap between the CMP sensor and camshaft sprocket changes. Permeability near sensor also changes. Due to the permeability change, magnetic flux near core is changed, and voltage signal generated in coil is changed. ECM receives voltage signal and detects cylinder number signal.