General Information

Engine Control
P0391 Camshaft Position Sensor - General Information

Component Location





General Description

The Camshaft Position Sensor (CMPS) is a Hall Effect sensor that tracks the camshaft position. The CMPS consists of a hall type sensor and a target on the end of the camshaft. When the target triggers the sensor, the sensor voltage is 5V. If not, the sensor voltage is 0V. These CMPS signal is sent to the ECM and the signal is for synchronizing the of sequential fuel injectors.

DTC Description

Checking oputput signals from CMP during engine running, if the expected number of cam tooth count is not observed, ECM sets P0391.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data




Fig.1) Normal waveforms of CMPS