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DTC P0C2C: Electric/Auxiliary Transmission Fluid Pump Control Module Feedback Signal Range/Performance: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

Trouble symptom: 

Auto Start Stop does not operate.

CAUTION:

Wiring diagram: 

CVT control system Ref. to WIRING SYSTEM>CVT CONTROL SYSTEM .

G13228223Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK REPEATABILITY  .
    1. Using the Subaru Select Monitor, perform the clear memory. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY .
    2. Start the engine.
    3. Operate Auto Start Stop after driving the vehicle, then restart the engine by pressing the Auto Start Stop cancel switch.
      NOTE: Even if Auto Start Stop does not operate, go to step 4)  .
    4. Turn the ignition switch to OFF and wait for 10 seconds.
    5. Using the Subaru Select Monitor, read the DTC after repeating the procedure from step  2 to  4 three times. Ref. to AUTO START STOP (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is the same DTC as current diagnosis output?

    Yes:  Go to  2.

    No:  The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

    NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause  .
  2. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL  .
    1. Turn the ignition switch to ON.
    2. Read the waveform of electric oil pump operation status signal using an oscilloscope.

      Connector & terminal 

      (T10) No. 7 (+) - Chassis ground (-):

    Is the duty ratio of electric oil pump operation status signal 30%? Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM .

    Yes:  Go to  4.

    No:  Go to  3.

  3. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL  .

    Read the waveform of electric oil pump operation command signal using an oscilloscope.

    Connector & terminal 

    (T10) No. 21 (+) - Chassis ground (-):

    Is the duty ratio of electric oil pump operation command signal 10%? Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM .

    Yes:  Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>ELECTRIC FLUID PUMP .

    No:  Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>TRANSMISSION CONTROL MODULE (TCM) .

  4. CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL  .
    1. Start the engine.
    2. Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. Ref. to AUTO START STOP (DIAGNOSTICS)>ACTIVE TEST .
    3. Read the waveform of electric oil pump operation status signal using an oscilloscope.

      Connector & terminal 

      (T10) No. 7 (+) - Chassis ground (-):

    Is the duty ratio of electric oil pump operation status signal 50%? Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM .

    Yes:  Check for poor contact of TCM connector. Replace the TCM if no fault is found. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>TRANSMISSION CONTROL MODULE (TCM) .

    No:  Go to  5.

  5. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL  .
    1. Start the engine.
    2. Perform the active test using Subaru Select Monitor to activate the Auto Start Stop. Ref. to AUTO START STOP (DIAGNOSTICS)>ACTIVE TEST .
    3. Read the waveform of electric oil pump operation command signal using an oscilloscope.

      Connector & terminal 

      (T10) No. 21 (+) - Chassis ground (-):

    Is the duty ratio of electric oil pump operation command signal as shown below? Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM .

    Except for WILDERNESS MODEL: 70%

    WILDERNESS MODEL: 55%

    Yes:  Check for the poor contact in TCM connector and electric oil pump connector. If no fault is found, replace the electric oil pump. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>ELECTRIC FLUID PUMP .

    No:  Check for the poor contact in TCM connector and electric oil pump connector. Replace the TCM if no fault is found. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>TRANSMISSION CONTROL MODULE (TCM) .