The Crankshaft Position Sensor (CKPS) is a hall effect type sensor that generates voltage using a sensor and a target wheel mounted on the crankshaft; there are 28 slots in the target wheel where one is longer than the others. When the slot in the wheel aligns with the sensor, the sensor voltage outputs low. When the metal (tooth) in the wheel aligns with the sensor, the sensor voltage outputs high. During one crankshaft rotation there are 28 rectangular signals and one longer signal. The ECM calculates engine RPM by using the sensor’s signal and controls the injection duration and the ignition timing. Using the signal differences caused by the longer slot, the ECM identifies which cylinder is at top dead center.
If CKPS cannot find reference mark 2 or more times during starting , P0335 is set .
Item
Detecting Condition
Possible Cause
DTC Strategy
Reference mark check (During cranking)
Poor connection
Open or short in signal circuit
CKPS
Enable Conditions
IG ON
Battery voltage > 6V
Threshold Value
Cam signal time interval < 1.2 sec
No reference position detected during cranking
Diagnostic Time
fault counter ? 4 Times
MIL ON Condition
3 Trip
This example shows a typical Crankshaft Position Sensor(CkPS) waveform at idle. The ECM controls the injection and ignition timing by using these signals.