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 PCM and used for determining the ignition timing along with CKP signal. CMPS makes Sequential Injection possible.
If signal input phase is abnormal PCM 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 | ● The count of Phase edges detection > 8 times | |
Threshold Value | ● Abnormal phase edges (High or Low) | |
Diagnostic Time | ||
MIL ON Condition | ● 2 driving cycle |
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.
