DTC P0340: Camshaft Position Sensor Circuit [01/2019 - 03/2019]: Description

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The cam position sensor for the intake camshaft (VV1 signal) consists of a magnet and MRE (Magneto Resistive Element).

The intake camshaft has a timing rotor for the cam position sensor. When the intake camshaft rotates, changes occur in the air gaps between the timing rotor and MRE, which affects the magnetic field. As a result, the resistance of the MRE material fluctuates. The cam position sensor converts the camshaft rotation data to pulse signals, uses the pulse signals to determine the camshaft angle, and sends it to the ECM. Then the ECM uses this data to control fuel injection duration and fuel injection timing.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P0340	Camshaft Position Sensor Circuit	One of the following conditions is met: No cam position sensor signal to the ECM while cranking (2 trip detection logic). No cam position sensor signal to the ECM at an engine speed of 600 rpm or higher (1 trip detection logic). A missing cam position sensor signal despite the crank position sensor inputs being normal at an engine speed of 600 rpm or more (1 trip detection logic).	Open or short in cam position sensor (for intake camshaft) circuit Cam position sensor (for intake camshaft) Camshaft housing sub-assembly ECM	Comes on	DTC stored

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Reference: Inspection using an oscilloscope.

HINT:

The correct waveform is as shown.
VV1 stands for the cam position sensor (for intake camshaft) signal, and EV1 stands for the cam position sensor (for exhaust camshaft) signal.

ECM Terminal Name	CH1: Between VV1+ and VV1- CH2: Between EV1+ and EV1-
Tester Range	5 V/DIV., 20 ms./DIV.
Condition	Idling with warm engine