DTC P1817: Manual Switch Circuit Low

DTC detecting condition:  Immediately at fault recognition

Trouble symptom: 

• Switching between M ←→ D is not possible.
• The combination meter display does not switch even after switching to the manual mode.

Wiring diagram:  AT control system Ref. to WIRING SYSTEM>AT CONTROL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK MANUAL MODE SWITCH  .
   1. Disconnect the TCM connector. (B81)
   2. Measure the resistance between harnesses.

      Terminal No.	Measuring condition	Standard
      (B81) No. 24 - Chassis ground	Select lever: M position	Less than 1 Ω
      (B81) No. 24 - Chassis ground	Select lever: Other than M position	10 kΩ or more

   Does the resistance indicate the standard value?

   Yes:  Go to  2.

   No:  Go to  3.

2. CHECK HARNESS  .
   1. Disconnect the connector of the shift position indicator. (i208)
   2. Disconnect the manual mode switch connector. (i145)
   3. Measure the resistance between harnesses.

      Terminal No.	Measuring condition	Standard
      (i208) No. 6 - (i145) No. 10	Always	Less than 1 Ω
      (i208) No. 6 - Chassis ground	Always	10 kΩ or more
      (i145) No. 10 - Chassis ground	Always	10 kΩ or more

   Does the resistance indicate the standard value?

   Yes:  Replace the TCM. Ref. to AUTOMATIC TRANSMISSION>TRANSMISSION CONTROL MODULE (TCM) .

   No:  Repair or replace the harness or connector.

3. CHECK MANUAL MODE SWITCH  .
   1. Measure the resistance between harnesses.

      Terminal No.	Measuring condition	Standard
      (i145) No. 10 - (i145) No. 11	Select lever: M position	Less than 1 Ω
      (i145) No. 10 - (i145) No. 11	Select lever: Other than M position	10 kΩ or more

   Does the resistance indicate the standard value?

   Yes:  Go to  4.

   No:  Replace the manual mode switch assembly. Ref. to CONTROL SYSTEMS>MANUAL MODE SWITCH .

4. CHECK HARNESS  .
   1. Measure the resistance between harnesses.

      Terminal No.	Measuring condition	Standard
      (B81) No. 24 - (i208) No. 6	Always	Less than 1 Ω
      (B81) No. 24 - Chassis ground	Always	10 kΩ or more
      (i208) No. 6 - Chassis ground	Always	10 kΩ or more

   Does the resistance indicate the standard value?

   Yes:  Replace the shift position indicator. Ref. to CONTROL SYSTEMS>SELECT LEVER .

   No:  Repair or replace the harness or connector.