Check the vehicle service manual for sensor type, pinout, and test specs
Inspect the cam position sensor, connector, wiring, and tone wheel for damage, corrosion, or looseness
Verify battery voltage and good engine ground
Turn ignition off and disconnect the sensor connector
Test sensor power supply at the connector with a multimeter
Test sensor ground continuity to chassis ground
For a Hall-effect sensor, check signal wire voltage while cranking or running
For a Hall-effect sensor, verify the signal switches between low and high voltage
For a magnetic/inductive sensor, measure resistance across the sensor terminals
For a magnetic/inductive sensor, check AC voltage output while cranking
Compare all readings to manufacturer specifications
Check for damaged, missing, or dirty reluctor/tone wheel teeth
Use an oscilloscope to verify a clean cam sensor waveform if available
Scan for diagnostic trouble codes and review live data
Clear codes and retest after repairs
Replace the sensor if readings are out of specification and wiring is confirmed good