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Camshaft Position Sensor (Method With Oscilloscope)

Disconnect the ground terminal from battery sensor. <Ref. to BATTERY , NOTE, Note.>
Prepare an oscilloscope.
Remove the engine control module (ECM). <Ref. to REMOVAL , Engine Control Module (ECM).>
Install the ST between the ECM and bulkhead harness and the engine harness. <Ref. to CAUTION , General Description.>
ST 18460AA030 CHECK BOARD
Connect the ground terminal to battery sensor. <Ref. to BATTERY , NOTE, Note.>

Connect the probe to ST.

Intake camshaft position sensor

Fig 1: Connecting Ground Terminal To Battery Sensor - Intake Camshaft Position Sensor
Courtesy of SUBARU OF AMERICA, INC.

Exhaust camshaft position sensor

Fig 2: Connecting Ground Terminal To Battery Sensor - Exhaust Camshaft Position Sensor

Courtesy of SUBARU OF AMERICA, INC.

Camshaft position sensor		Terminal No.	Probe
Intake	RH	20	+
Intake	LH	21	+
Exhaust	RH	32	+
Exhaust	LH	33	+
RH and LH		34	-

Start the engine and let it idle.
Check the pattern is the same as the waveform and voltage shown below.

Fig 3: Crankshaft Rotation Voltage Waveform
Courtesy of SUBARU OF AMERICA, INC.
After inspection, install the related parts in the reverse order of removal.