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 CMPS signal is sent to the PCM and it uses CMPS signals for determining the ignition timing with CKPS signals. CMPS makes Sequential Injection possible.
If the signal input is low with no phase edge PCM sets DTC P0342.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Signal check, Low | ● Poor connection ● Short to ground in signal circuit ● CMPS |
Enable Conditions | ● Sensor signal requested | |
Threshold Value | ● Signal low and no phase edge | |
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.
