Circuit Description

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The Camshaft Position (CMP) sensor is a hall effect switching device that works in conjunction with a single tooth reluctor wheel used to determine the position of the bank 2 exhaust camshaft. The Engine Control Module (ECM) expects the CMP sensor signal to be low, zero volts, as the single tooth in the reluctor wheel passes the sensor and high, 12 volts, during the remainder of the reluctor wheel rotation. The ECM supplies a 12-volt pull up voltage on the CMP sensor signal circuit. The ECM expects to see one transition from high to low every 2 crankshaft revolutions. This signal, when combined with the Crankshaft Position (CKP) sensor signal, enables the ECM to properly synchronize ignition timing, fuel delivery and knock control. As long as the CKP signal is available, the engine can start and run. The ECM will default to a non-sequential fuel injector operation even if there is no CMP sensor signal. If ECM detects extra or missing CMP sensor signal transitions within a certain number of crankshaft revolutions, DTC P0341 sets.

The CMP sensor has the following circuits: Ignition 1 voltage circuit, low reference circuit and CMP sensor signal circuit.