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A/T

DTC P1121 - NEUTRAL POSITION SWITCH CIRCUIT LOW INPUT

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

TROUBLE SYMPTOM:
- Erroneous idling

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.

Wiring Diagram:





WIRING DIAGRAM

11BV1: CHECK DTC P0705 ON DISPLAY.

CHECK: Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0705?

YES: Inspect DTC P0705 using "11. Diagnostics Chart with Trouble Code for AT Vehicles".

NO: Go to step 11BV2.

11BV2:CHECK INPUT SIGNAL FOR ECM.

1. Turn ignition switch to ON.

Connector & Terminal - [(B135) No.26 (+) - Chassis Ground (-)]:





2. Measure voltage between ECM and chassis ground.

CHECK: Is the voltage between 4.5 and 5.5 V at except "N" and "P" positions?

YES: Even if MIL lights up, the circuit has returned to a normal condition at this time.

NO: Go to step 11BV3.

11BV3: CHECK HARNESS BETWEEN ECM AND TRANSMISSION HARNESS CONNECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connectors from ECM and transmission harness connector (T3).

Connector & Terminal - [(B135) No.26 - Chassis Ground]:





3. Measure resistance of harness between ECM connector and chassis ground.

CHECK: Is the resistance less than 10 Ohms?

YES: Repair ground short circuit in harness between ECM and transmission harness connector.

NO: Go to step 11BV4.

11BV4: CHECK TRANSMISSION HARNESS CONNECTOR.

1. Disconnect connector from inhibitor switch.

Connector & Terminal - [(T3) No.12 - Engine Ground]:





2. Measure resistance of harness between transmission harness connector and engine ground.

CHECK: Is the resistance less than 10 Ohms?

YES: Repair ground short circuit in harness between transmission harness and inhibitor switch connector.

NO: Go to step 11BV5.

11BV5: CHECK INHIBITOR SWITCH.

Terminals [No.7 - No.12]:





Measure resistance between inhibitor switch connector receptacle's terminals in selector lever except for "N" position.

CHECK: Is the resistance more than 1 M.Ohms at except "N" and "P" positions?

YES: Go to step 11BV6.

NO: Replace inhibitor switch.

11BV6: CHECK SELECTOR CABLE CONNECTION.

CHECK: Is there any fault in selector cable connection to inhibitor switch?

YES: Repair selector cable connection.

NO: Contact with Subaru of America (SOA) service.

NOTE: Inspection by Subaru of America's DTM is required, because probable cause is deterioration of multiple parts.