Operation CHARM: Car repair manuals for everyone.

General Information





Component Location





General Description

The Camshaft Position Sensor (CMPS) is a sensor that detects the compression TDC of the NO. 1 cylinder. The CMPS consists of a hall type sensor and a target on the end of the intake 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 PCM and the PCM uses the CMPS signal for synchronizing the firing of sequential fuel injectors.

DTC Description

If PCM detects that cam event signal count is over 3 under detecting condition, PCM sets P0340. MIL (Malfunction Indication Lamp) turns on.

DTC Detecting Condition





Diagnostic Circuit





Signal Waveform




Fig) Signal waveform of CKPS and CMPS at idle

This example shows a typical Crankshaft Position Sensor (CKPS) and Camshaft Position Sensor (CMPS) waveform at idle. The PCM controls the injection and ignition timing by using these signals. Generally CKPS signal is used to detect the piston's position and CMPS signal is used to detect the Top Dead Center of each cylinder.