Turbine Speed Sensor: Inspection

Disconnect the ground terminal from battery sensor. < Ref. to BATTERY , NOTE, Repair Contents. >
Remove the clip (A), and loosen the clamps (B) and (C).

Fig 1: Identifying Air Intake Boot Clip And Clamps
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Remove the air intake boot from the throttle body, and move it to the left side wheel apron.

Fig 2: Identifying Air Cleaner Case (Rear) And Throttle Body
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Disconnect the transmission radio ground terminal and transmission harness connector, and remove the harness clip.

Fig 3: Identifying Transmission Radio Ground Terminal And Harness Connector
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Remove the transmission case cover.

Fig 4: Locating Transmission Case Cover Bolts
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Move the lock lever in the arrow direction while pressing the lock button, and disconnect the connector.

Fig 5: Moving Lock Lever
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Set the ST between TCM and transmission harness. < Ref. to CAUTION , General Description. >
ST 18460AA040 CHECK BOARD
Connect the transmission radio ground terminal and transmission harness connector, and install the harness clip.
Tightening torque:

13 N.m (1.3 kgf-m, 9.6 ft-lb)
Install the air intake boot assembly. < Ref. to INSTALLATION , Air Intake Boot. >
Connect the ground terminal to battery sensor. < Ref. to BATTERY , NOTE, Repair Contents. >
Set the probe of oscilloscope to the check board connector.
Connector & terminal:

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

Fig 6: Identifying Board Connector Terminals
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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.

Fig 7: Turbine Speed Sensor Output Voltage Signal Waveform
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