DTC P0340: Camshaft Position Sensor: Description

WARNING: This page is about a different car, the 2002 Nissan Xterra and 2002 Nissan Frontier. However, it is still accessible from the selected car via links, so may be relevant.

The Camshaft Position (CMP) sensor is a basic component of the engine control system. It monitors engine speed and piston position. It monitors engine speed and piston position. These input signals to the engine control system are used to control fuel injection, ignition timing and other functions.

The CMP sensor has a rotor plate and a wave-forming circuit. The rotor plate has 360 slits for a one-degree signal and 4 slits for a 180-degree signal (on 2.4L models) or 6 slits for a 120-degree signal (on 3.3L models). The wave-forming circuit consists of LEDs and photo diodes.

The rotor plate is positioned between the LED and the photo diode. The LED transmits light to the photo diode. As the rotor plate turns, the slits cut the light to generate rough-shaped pulses. These pulses are converted to on-off signals by the wave-forming circuit and sent to the ECM.

The distributor is not repairable and must be replaced as an assembly except for distributor cap and rotor.