DTC P0708 Transmission Range Sensor "A" Circuit High: Notes

DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Shift characteristics are erroneous.
The range position of the select lever and the position of shift indicator display do not match.

CAUTION: Use CHECK BOARD when measuring the TCM terminal voltage and resistance.

Wiring diagram:

Non-turbo model
CVT control system Ref. to WIRING SYSTEM>CVT Control System>WIRING DIAGRAM>NON-TURBO MODEL .

Fig 1: Transmission Range Sensor (A) Circuit High System Wiring Diagram (Non-Turbo Model)
Courtesy of SUBARU OF AMERICA, INC.
Turbo model
CVT control system Ref. to WIRING SYSTEM>CVT Control System>WIRING DIAGRAM>TURBO MODEL .

Fig 2: Transmission Range Sensor (A) Circuit High System Wiring Diagram (Turbo Model)

Courtesy of SUBARU OF AMERICA, INC.

CHECK INPUT SIGNAL FOR TCM.
1. Turn the ignition switch to ON.
2. Move the select lever to each range, read the data of [P Range], [R Range Signal], [N Range] and [D Range Signal] using the Subaru Select Monitor.
Is the display of the corresponding range "ON"?
- Yes : Go to 7.
- No : Go to 2.
CHECK HARNESS.
1. Turn the ignition switch to OFF.
2. Disconnect the TCM connector.
3. Disconnect the transmission connector.
4. Measure the resistance of harness between TCM connector and transmission connector.
  Connector & terminal
  
  Non-turbo model
  
  (B54) No. 38 - (B12) No. 1:
  
  (B54) No. 37 - (B12) No. 2:
  
  (B54) No. 36 - (B12) No. 3:
  
  (B54) No. 35 - (B12) No. 4:
  
  Turbo model
  
  (B54) No. 38 - (B12) No. 3:
  
  (B54) No. 37 - (B12) No. 2:
  
  (B54) No. 36 - (B12) No. 1:
  
  (B54) No. 35 - (B12) No. 8:
Is each resistance less than 1 Ω?
- Yes : Go to 3.
- No : Repair the open circuit of body harness.
CHECK HARNESS.
Measure the resistance of harness between inhibitor switch connector and transmission ground.

Connector & terminal

(T7) No. 1 - Transmission ground:

Is the resistance less than 1 Ω?
- Yes : Go to 4.
- No : Repair the open circuit of harness.
CHECK HARNESS.
1. Disconnect the inhibitor switch connector.
2. Measure the resistance between transmission connector and inhibitor switch connector.
  Connector & terminal
  
  Non-turbo model
  
  (T3) No. 1 - (T7) No. 2:
  
  (T3) No. 2 - (T7) No. 5:
  
  (T3) No. 3 - (T7) No. 3:
  
  (T3) No. 4 - (T7) No. 4:
  
  Turbo model
  
  (T3) No. 3 - (T7) No. 2:
  
  (T3) No. 2 - (T7) No. 5:
  
  (T3) No. 1 - (T7) No. 3:
  
  (T3) No. 8 - (T7) No. 4:
Is each resistance less than 1 Ω?
- Yes : Go to 5.
- No : Repair the open circuit of transmission harness.
CHECK INHIBITOR SWITCH.
Move the select lever to each range, and measure the resistance between inhibitor switch terminals.

Terminals

No. 2 - No. 1:

No. 5 - No. 1:

No. 3 - No. 1:

No. 4 - No. 1:

Is the resistance of the corresponding range less than 1 MΩ?
- Yes : Go to 6.
- No : Replace the inhibitor switch. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Inhibitor Switch . Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR690)>Inhibitor Switch .
CHECK HARNESS.
1. Turn the ignition switch to ON.
2. Measure the voltage between each connector and chassis ground.
  Connector & terminal
  
  Transmission connector (B12 side)
  
  Non-turbo model
  
  (B12) No. 1 (+) - Chassis ground (-):
  
  (B12) No. 2 (+) - Chassis ground (-):
  
  (B12) No. 3 (+) - Chassis ground (-):
  
  (B12) No. 4 (+) - Chassis ground (-):
  
  Turbo model
  
  (B12) No. 3 (+) - Chassis ground (-):
  
  (B12) No. 2 (+) - Chassis ground (-):
  
  (B12) No. 1 (+) - Chassis ground (-):
  
  (B12) No. 8 (+) - Chassis ground (-):
  
  Transmission connector (T7 side)
  
  (T7) No. 2 (+) - Chassis ground (-):
  
  (T7) No. 5 (+) - Chassis ground (-):
  
  (T7) No. 3 (+) - Chassis ground (-):
  
  (T7) No. 4 (+) - Chassis ground (-):
Is each voltage less than 1 V?
- Yes : Go to 7.
- No : Repair the harness which outputs 1 V or more.
CHECK FOR POOR CONTACT.
Is there poor contact between TCM, inhibitor switch, transmission ground?
- Yes : Repair the poor contact.
- No : Replace the TCM. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR580)>Transmission Control Module (TCM) . Ref. to CONTINUOUSLY VARIABLE TRANSMISSION(TR690)>Transmission Control Module (TCM) .