DTC P173C: Electric Fluid Pump (CVT) Status Circuit Low: 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) .

G13630226

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 .

G13630227

Courtesy of SUBARU OF AMERICA, INC.

CAUTION:

Use the check board when measuring the TCM terminal voltage and resistance.
After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. Ref. to AUTO START STOP (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

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. Measure the resistance between TCM connector and chassis ground.
  Connector and terminal
  
  ENGINE TYPE FB
  
  (T21) No. 7 - Chassis ground:
  
  ENGINE TYPE FA
  
  (B67) No. 7 - Chassis ground:
Is the resistance 1 MΩ or more?

Yes: Go to 2 .

No: Repair the short circuit to ground in the harness between TCM and electric oil pump connector.
CHECK ELECTRIC OIL PUMP OPERATION STATUS SIGNAL .
1. Connect the TCM connector.
2. Turn the ignition switch to ON.
3. Read the waveform of electric oil pump operation status signal using an oscilloscope.
  Connector and terminal
  
  ENGINE TYPE FB
  
  (T21) No. 7 (+) - Chassis ground (-):
  
  ENGINE TYPE FA
  
  (B67) No. 7 (+) - Chassis ground (-):
Is the duty ratio of electric oil pump operation status signal 100%? 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) .