Camshaft Position Sensor (Except Maxima & Sentra 1.8L)

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2000 Nissan Xterra, 2000 Nissan Sentra, 2000 Nissan Quest, 2000 Nissan Pathfinder, and 2000 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

CMP sensor monitors engine speed and piston position. CMP sensor, which is built into distributor, has a rotor plate and a wave-forming circuit. Rotor plate has 360 small outer slits (one degree apart) to determine engine speed and 4 (4-cylinder) or 6 (V6) larger inner signal slits, 90 (4-cylinder) or 60 (V6) degrees apart, to determine camshaft position. See Fig 1. The signal slit for cylinder No. 1 is the largest inner signal slit to allow ECM to determine TDC for cylinder No. 1.

When signal rotor plate passes space between Light Emitting Diode (LED) and photo diode, slits in signal rotor plate alternately cuts light from LED to photo diode. This causes a pulsating voltage, which is converted into an on-off pulse by wave-forming circuit and sent to ECM. ECM uses this signal to control fuel injection, ignition timing and other functions.

Fig 1: Identifying Camshaft Position Sensor (Typical - Except Maxima & Sentra 1.8L)

Courtesy of NISSAN MOTOR CO., U.S.A.