Turbine Speed Sensor: Inspection

WARNING: This page is about a different car, the 2020 Subaru Impreza. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the ground terminal from 12V engine restart battery sensor. Refer to REPAIR CONTENTS>REPAIR CONTENTS>NOTE>BATTERY .
Remove the clip from the air intake boot, and loosen the clamp.

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Remove the air intake boot, and place it aside so that it does not interfere with the work.
NOTE: Be careful not to pull out the PCV hose.

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Remove the transmission radio ground terminal.

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Disconnect the transmission harness connector.

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Remove the transmission case cover (small).

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Move the lock lever in the arrow direction while pressing the lock button, and disconnect the connector.

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Set the ST between the TCM and transmission harness. Refer to TRANSMISSION (DIAGNOSTICS) (IMPREZA MODEL)>GENERAL DESCRIPTION>CAUTION .
Preparation tool:

ST: CHECK BOARD (18460AA040)
Connect the transmission radio ground terminal and transmission harness connector.
Tightening torque:

32.3 N.m (3.3 kgf-m, 23.8 ft-lb)
Install the air intake boot. Refer to INTAKE (INDUCTION) (H4DO (EXCEPT FOR HEV))>AIR INTAKE BOOT>INSTALLATION .
Connect the ground terminal to 12V engine restart battery sensor. Refer to REPAIR CONTENTS>REPAIR CONTENTS>NOTE>BATTERY .
Set the probe of oscilloscope to the check board connector.
Connector & terminal

(B54) No. 12 (+) - No. 26 (-):

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Start and warm up the engine.
Check the waveform and output voltage of the turbine speed sensor with engine idling.
NOTE: The waveform cycle changes as the speed changes.

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