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Throttle Sensor (Method With Circuit Tester)

NOTE: Individual difference of the accelerator pedal may not be corrected sufficiently on the ECM side after DTCs were cleared or the battery was removed and installed on the vehicle. Therefore, when the reference voltage is not reached after following the procedure, repeat the ignition switch ON (engine OFF) and ignition switch OFF operations 40 times at intervals of three seconds or more, and then measure the voltage again.
  1. Disconnect the ground terminal from battery sensor. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
  2. Disconnect the connector from ECM. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>ENGINE CONTROL MODULE (ECM)>REMOVAL .
  3. Attach the ST between the ECM, engine wiring harness and the bulkhead wiring harness. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

    Special tool: 

    CHECK BOARD (18460AA180)

  4. Connect the ground terminal to battery sensor. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
  5. Start the engine and wait for 10 seconds or more.
  6. Stop the engine.
  7. Turn the ignition switch to ON within 4 to 5 seconds. (Engine OFF)
  8. Check the voltage between ECM connector terminals when accelerator pedal is fully closed and fully open.

    Check 

    • When voltage is within standard values  → Normal
    • When voltage is not within standard values  → It is possible that there is a connector connection failure, harness open circuit, short circuit, or malfunction of the throttle body. Perform inspection or replacement.
    • If throttle sensor voltage does not change when the accelerator pedal is fully open  → Go to step 9.
    G13223826Courtesy of SUBARU OF AMERICA, INC.
    Throttle sensor Accelerator pedal Terminal No. Standard
    Main Not depressed (full closed) 29 (+) and 30 (-) Approx. 0.6 - 1.2 V
    Depressed (full opened) Approx. 3.8 - 4.4 V
    Sub Not depressed (full closed) 43 (+) and 30 (-) Approx. 1.4 - 2.0 V
    Depressed (full opened) Approx. 4.0 - 4.6 V
  9. If throttle sensor voltage did not change when the accelerator pedal was fully open in step 8, perform the following procedure.
    1. Using the Subaru Select Monitor or general scan tool, read and check the DTC.
      NOTE: Because a DTC is detected when inspection was performed with the connector disconnected from the TCM, this procedure is required in order to identify the detected DTC.
    2. Turn the ignition switch to OFF.
    3. Disconnect the ground terminal from battery sensor. Ref. to REPAIR CONTENTS>NOTE > BATTERY .
    4. Disconnect the connector from TCM. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>TRANSMISSION CONTROL MODULE (TCM)>REMOVAL .
    5. Connect the ground cord.

      Tightening torque: 

      32.3 N.m (3.3kgf-m, 23.8ft-lb)

      G13950407Courtesy of SUBARU OF AMERICA, INC.
    6. Connect the ground terminal to battery sensor. Ref. to REPAIR CONTENTS>NOTE > BATTERY .
    7. Turn the ignition switch to ON. (Engine OFF)
    8. Check the voltage between ECM connector terminals when accelerator pedal is fully closed and fully open.

      Check 

      • When voltage is within standard values  → Normal
      • When voltage is not within standard values  → It is possible that there is a connector connection failure, harness open circuit, short circuit, or malfunction of the throttle body. Perform inspection or replacement
      • If throttle sensor voltage does not change  → Go to step 10.
  10. Start the engine.
  11. Check the voltage between ECM connector terminals when accelerator pedal is fully closed and fully open.
    CAUTION: When depressing the accelerator pedal to fully open, perform it in as short a time as possible, but within the range where the inspection result is not adversely affected.
    NOTE: Perform the inspection in the following conditions.
    • Select lever is in "P" range.
    • Parking brake activated

    Check 

    When voltage is within standard values  → Normal

    When voltage is not within standard values → It is possible that there is a connector connection failure, harness open circuit, short circuit, or malfunction of the throttle body. Perform inspection or replacement.

  12. After inspection, install the related parts in the reverse order of removal.
    NOTE:
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