DTC P0340: Camshaft Position Sensor - Circuit Malfunction: Reference

WARNING: This page is about a different car, the 2002 Suzuki Esteem. However, it is still accessible from the selected car via links, so may be relevant.

To test CPM sensor with an oscilloscope, connect oscilloscope to ECM by backprobing ECM harness connector C20 terminal No. 22 (Yellow/Green wire) and ECM harness connector C99 terminal No. 26 (Purple wire). See Figure . Compare CKP sensor waveform, to waveform in illustration. See Fig 1 .

Fig 1: Identifying Camshaft Position Sensor Waveform

Courtesy of SUZUKI OF AMERICA CORP.