DTC P1739: Electric Fluid Pump (CVT) Drive Circuit: Notes

1. - 

DTC detecting condition: 

Detected when three consecutive driving cycles with fault occur.

Trouble symptom: 

Auto Start Stop does not operate.

Wiring diagram: 

• ENGINE TYPE FB

CVT control system Ref. to WIRING SYSTEM>CVT CONTROL SYSTEM>WIRING DIAGRAM>ENGINE TYPE FB .

Fuse and relay Ref. to WIRING SYSTEM>FUSE AND RELAY>LOCATION>ENGINE COMPARTMENT SIDE (ENGINE TYPE FB) .

Courtesy of SUBARU OF AMERICA, INC.

• ENGINE TYPE FA

  CVT control system Ref. to WIRING SYSTEM>CVT CONTROL SYSTEM>WIRING DIAGRAM>ENGINE TYPE FA .

  Fuse and relay Ref. to WIRING SYSTEM>FUSE AND RELAY>LOCATION>PASSENGER ROOM SIDE .

Courtesy of SUBARU OF AMERICA, INC.

(B)

1. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the TCM connector.
   3. Disconnect the connector of electric oil pump.
   4. Turn the ignition switch to ON.
   5. Measure the voltage between TCM connector and chassis ground.

      Connector and terminal 

      ENGINE TYPE FB

      (T21) No. 21 (+) - Chassis ground (-):

      ENGINE TYPE FA

      (B67) No. 21 (+) - Chassis ground (-):

   Is the voltage 10 V or more?

   Yes:  Repair the short circuit to power supply in the harness between TCM and electric oil pump connector.

   No:  Go to  2 .

2. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR  .
   1. Turn the ignition switch to OFF.
   2. Measure the resistance between TCM connector and chassis ground.

   Connector and terminal 

   ENGINE TYPE FB

   (T21) No. 21 - Chassis ground:

   ENGINE TYPE FA

   (B67) No. 21 - Chassis ground:

   Is the resistance 1 MΩ or more?

   Yes:  Go to  3 .

   No:  Repair the short circuit to ground in the harness between TCM and electric oil pump connector.

3. CHECK HARNESS BETWEEN TCM AND ELECTRIC OIL PUMP CONNECTOR  .

   Measure the resistance in harness between TCM connector and electric oil pump connector.

   Connector and terminal 

   ENGINE TYPE FB

   (T21) No. 21 - (T51) No. 3:

   ENGINE TYPE FA

   (B67) No. 21 - (T51) No. 3:

   Is the resistance less than 1 Ω?

   Yes:  Go to  4 .

   No:  Repair the open circuit in harness between TCM connector and electric oil pump connector.

4. CHECK ELECTRIC OIL PUMP OPERATION COMMAND SIGNAL  .
   1. Connect all connectors.
   2. Turn the ignition switch to ON.
   3. Read the waveform of electric oil pump operation command signal using an oscilloscope.

      Connector and terminal 

      ENGINE TYPE FB

      (T21) No. 21 (+) - Chassis ground (-):

      ENGINE TYPE FA

      (B67) No. 21 (+) - Chassis ground (-):

   Is the duty ratio of electric oil pump operation command signal 5 - 95%? Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM .

   Yes:  Replace the electric oil pump. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>ELECTRIC FLUID PUMP . Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>ELECTRIC FLUID PUMP .

   No:  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) . Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TRANSMISSION CONTROL MODULE (TCM) .