Primary 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: Air Intake Duct 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: Air Intake Boot
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Disconnect the transmission radio ground terminal and transmission harness connector, and remove the harness clip.

Fig 3: Locating Harness Clip
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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. 14 (+) - No. 42 (-):

Fig 6: Board Connector Terminals
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Start and warm up the engine.
Lift up the vehicle.
CAUTION: Lift up the vehicle until the tire bottom is 0.3 m (0.98 ft) or more above the ground.
Shift the select lever to "D" range.
Check the waveform and output voltage of the primary speed sensor with engine idling.

NOTE: The waveform cycle changes as the speed changes.

Fig 7: Waveform Cycle - Primary Speed Sensor

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