Camshaft Position Sensor (Method With Oscilloscope)

Disconnect the ground cable from battery.
Prepare an oscilloscope.
While pressing the section (A) shown in the figure, move the lock lever (B) in the direction of the arrow to disconnect the connectors from the ECM in numerical order as shown in the figure.

Fig 1: Moving Lock Lever
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Install the special tool between the ECM and body harness and the engine harness. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>General Description>CAUTION .
ST 18460AA030 CHECK BOARD
Connect the battery ground terminal.

Connect the probe to ST.

Fig 2: Checking Waveforms And Voltage (Intake Camshaft Position Sensor)

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Fig 3: Checking Waveforms And Voltage (Exhaust Camshaft Position Sensor)

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Start the engine and let it idle.
Check the waveforms and voltage.
NOTE: For waveform and voltage, refer to "Control Module I/O Signal". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>Engine Control Module (ECM) I/O Signal>ELECTRICAL SPECIFICATION .
After inspection, install the related parts in the reverse order of removal.