DTC P0340: Camshaft Position Sensor - Circuit Malfunction: Reference

Backprobing at ECM, connect oscilloscope between ECM connector C20 terminal No. 2 (Black/White wire) and ECM connector C21 terminal No. 1 (Black wire). See Figure . Compare CPM sensor waveform, to waveform in illustration. See Fig 1 .

Fig 1: Identifying Camshaft Position Sensor Waveforms

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