DTC P0340: Camshaft Position Sensor Circuit: Description
WARNING: This page is about a different car, the 2003 Cadillac Seville and 2003 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) uses the Camshaft Position (CMP) sensor high resolution signal in order to determine the position of the valve train in relation to the engine cylinders. The PCM uses the CMP high resolution signal in order to sequence the ignition system and the fuel injectors. The PCM supplies a 12-volt reference and a low reference to the CMP sensor. The CMP sensor returns a signal pulse in response to the reluctor track, located on the camshaft sprocket. If during operation, the PCM detects a loss of CMP sensor high resolution signal, DTC P0340 will set.