Camshaft Position Sensor (CMPS) is a hall sensor and detects the camshaft position by using a hall element. It is related with Crankshaft Position Sensor (CKPS) and detects the piston position of the each cylinder which the CKPS can’t detect. The CMPS are installed on engine head cover and uses a target wheel installed on the camshaft. This sensor has a hall-effect IC which output voltage changes when magnetic field is made on the IC with current flow. When teeth on the target wheel trigger the sensor, output voltage is 12V. If not, it is 0V. These CMP signal is sent to the ECM and used for determining the ignition timing along with CKP signal. CMPS makes Sequential Injection possible.
If signal input phase is abnormal ECM sets DTC P0340.
Item
Detecting Condition
Possible Cause
DTC Strategy
Sensor wrong mounted. (check the assembling state)
Poor connection
abnormal assembling state
CMPS
Enable Conditions
No CKP sensor error
Gap of CKP sensor wheel detected
Threshold Value
Counter of failure to detect toggling of phase signal level at consecutive gaps = 5
Diagnostic Time
Continuous
MIL ON Condition
NO MIL
This example shows a typical Crankshaft Position Sensor(CKPS) and Camshaft Position Sensor(CMPS) waveform at idle. The ECM controls the injection and ignition timing by using these signals. Generally CKPS signal is used to detect the piston’s position an.