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Primary Speed Sensor: Inspection

  1. Check for oil leaks.
  2. Check the output waveform and output voltage of the primary speed sensor.
    1. Disconnect the ground terminal from battery sensor. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
    2. Disconnect the connector from TCM. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>Transmission Control Module (TCM)>REMOVAL .
    3. Set the ST between TCM and connector. Ref. to TRANSMISSION (DIAGNOSTICS)>General Description>CAUTION .

      Special tool: 

      CHECK BOARD (18460AA040)

    4. Connect the ground terminal to battery sensor. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
    5. Connect the probe of oscilloscope to ST.
      G13225684Courtesy of SUBARU OF AMERICA, INC.
      Terminal No. Probe
      14 +
      42 -
    6. Start the engine and warm up completely.
    7. Check the output waveform and output voltage with engine idling.
      NOTE: For the output waveform and output voltage, refer to "TRANSMISSION (DIAGNOSTICS)". Ref. to TRANSMISSION (DIAGNOSTICS)>Transmission Control Module (TCM) I/O Signal>SENSOR .
  3. After inspection, install the related parts in the reverse order of removal.