The Crankshaft Position (CKP) sensor system consists of a CKP sensor plate and a pickup coil. The sensor plate has 34 teeth and is installed on the crankshaft. The pickup coil is made of wound copper wire, an iron core and magnet. The sensor plate rotates and, as each tooth passes through the pickup coil, a pulse signal is created. The pickup coil generates 34 signals per engine revolution. Based on these signals, the ECM calculates the crankshaft position and engine RPM. Using these calculations, the fuel injection time and ignition timing are controlled.


DTC Detection Condition

Trouble Area


When either condition below is met:

• No CKP sensor signal to ECM while cranking (1 trip detection logic)

• No CKP sensor signal to ECM at engine speed of 600 rpm or more (1 trip detection logic)

• Open or short in CKP sensor circuit

• CKP sensor plate



Under conditions (a), (b) and (c), no CKP sensor signal to ECM for 0.05 seconds or more (1 trip detection logic):

(a) Engine speed 1,000 rpm or more

(b) Starter signal OFF

(c) 3 seconds or more have elapsed since starter signal switched from ON to OFF

• Open or short in CKP sensor circuit

• CKP sensor plate


Reference: Inspection using an oscilloscope.

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• The correct waveform is as shown.

• G2+ stands for the Camshaft Position (CMP) sensor signal, and NE+ stands for the CKP sensor signal.

• Grounding failure of the shielded wire may cause noise in waveforms.




CH1: G2+ - G2-CH2: NE+ - NE-

Equipment Settings

5 V/Division, 20 ms./Division


Cranking or idling

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