Camshaft Position Sensor "A" Circuit (Bank 1 or Single Sensor)


The Camshaft Position (CMP) sensor consists of a magnet and an iron core which is wrapped with copper wire, and is installed onto the cylinder head. When the camshaft rotates, each of 3 teeth on the camshaft passes through the CMP sensor. This activates the internal magnet in the sensor, generating a voltage in the copper wire. The camshaft rotation is synchronized with the crankshaft rotation. When the crankshaft turns twice, the voltage is generated 3 times in the CMP sensor. The generated voltage in the sensor acts as a signal, allowing the ECM to locate the camshaft position. This signal is then used to control ignition timing, fuel injection timing, and the VVT system.


DTC Detection Conditions

Trouble Areas

• No Camshaft Position (CMP) sensor signal to ECM while cranking (2 trip detection logic)

Case 2

• Camshaft/Crankshaft misalignment detected at engine speed of 600 rpm or more (1 trip detection logic)

• Open or short in CMP sensor circuit

• Jumped tooth of timing chain

DTC P0340 indicates a malfunction relating to the CMP sensor (+) circuit (the wire harness between the ECM and CMP sensor, and the CMP sensor itself). Reference: Inspection using an oscilloscope

1 1 1 1 v-V

1 1 1 1

1 1 1 1 1 -


• The correct waveform is as shown in the illustration.

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

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




CHI: G2+ - G2-CH2: NE+ - NE-

Equipment Settings

5 V/Division, 20 ms/Division


Cranking or idling


If no signal is transmitted by the CMP sensor despite the engine revolving, or the rotation of the camshaft and the crankshaft is not synchronized, the ECM interprets this as a malfunction of the sensor.

If the malfunction is not repaired successfully, a DTC is set 10 seconds after the engine is next started.


Related DTCs

P0340: Camshaft position sensor range check

P0340: Camshaft position/crankshaft position misalignment

Required Sensors/Components (Main)

Camshaft Position (CMP) sensor

Required Sensors/Components (Related)

Crankshaft Position (CKP) sensor

Frequency of Operation



4 seconds: CMP sensor range check

5 seconds: Camshaft position/crankshaft position misalignment

MIL Operation

2 driving cycles: CMP sensor range check

Immediate: Camshaft position/crankshaft position misalignment

Sequence of Operation


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