DTC P0712: Transmission Fluid Temperature Sensor "A" Circuit Low: Notes

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

• Excessive shift shock
• Shift characteristics malfunction
  CAUTION: Use the check board when measuring the TCM terminal voltage and resistance.

Wiring diagram: 

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

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK HARNESS. 
   1. Turn the ignition switch to OFF.
   2. Disconnect the TCM connector.
   3. Measure the resistance of harness between TCM connector and chassis ground.

      Connector & terminal 

      (B54) No. 1 - Chassis ground:

      (B54) No. 6 - Chassis ground:

   Is the resistance 1 MΩ or more?

   Yes:  Go to  4.

   No:  Go to  2.

2. CHECK HARNESS. 
   1. Disconnect the transmission connector.
   2. Measure the resistance between transmission connector and transmission body.

      Connector & terminal 

      (T4) No. 16 - Transmission body:

      (T4) No. 19 - Transmission body:

   Is the resistance 1 MΩ or more?

   Yes:  Repair the short circuit of body harness.

   No:  Go to  3.

3. CHECK HARNESS INSIDE TRANSMISSION. 
   CAUTION: Start work after ATF cools down.
   1. Remove the transmission oil pan.
   2. Check for the harness pinch, damage.

   Is there any fault in the harness?

   Yes:  Replace the transmission harness.

   No:  Go to  4.

4. CHECK ATF TEMPERATURE SENSOR. 

   Measure the resistance between transmission connector terminals.

   Connector & terminal 

   (T4) No. 16 - No. 19:

   NOTE: Perform the measurements using multiple oil temperatures.

   Is resistance as follows?

   Fluid temperature 0°C → Approx. 6.2 kΩ

   Fluid temperature 20°C → Approx. 2.6 kΩ

   Fluid temperature 80°C → Approx. 370 Ω

   Yes:  Replace the TCM. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TRANSMISSION CONTROL MODULE (TCM) .

   No:  Replace the control valve body. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>CONTROL VALVE BODY .