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 ECM and the ECM uses the CMPS signal for synchronizing the firing of sequential fuel injectors.
The ECM monitors the camshaft sensor signal tranisiton position which must change only once per crankshaft revolution.If no camshaft signal is detected while crankshaft signal is detected, the ECM sets DTC P0340.If same error code is set in the next driving cycle, the ECM illuminates the MIL.
Item
Detecting Condition
Possible cause
Monitoring Strategy
? Signal check
? Open in signal circuit
? Open in battery and ground circuit
? Short to ground in signal circuit
? Short to battery in signal circuit
? Faulty CMPS
? Faulty ECM
Threshold value
? Signal high and no phase edge : 12 times
? Signal low and no phase edge : 12 times
? Irregular phase edge : 12times
Enable Conditions
? Sensor signal requested
Diagnostic Time
Fail Safe
? The normal serial fuel injection starts with crankshaft sensor signal.
? Ignition timing is retarded.
Normal Parameter
Idle rpm
3000rpm
Signal Voltage
0 ~ B+( 5 ~ 8Hz )
0 ~ B+( 24 ~ 8Hz )26
This figure shows the waveform measured at terminal 2 of CMPS.
Make sure there is any missing tooth or noise while changing RPM.
The waveform must be displayed regurally.
HI level at point ? should be over 4.1V and LOW level at point ? should be below 0.8V.