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P0117

I: DTC P0117-ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Immediately at fault recognition

TROUBLE SYMPTOM:
- Hard to start.
- Erroneous idling.
- Poor driving performance.

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





WIRING DIAGRAM

10I1: CONNECT SUBARU SELECT MONITOR OR THE OBD-II GENERAL SCAN TOOL, AND READ DATA.
1) Turn ignition switch to OFF.





2) Connect Subaru Select Monitor or the OBD-II general scan tool to data link connector.

3) Turn ignition switch to ON and Subaru Select Monitor or OBD-II general scan tool switch to ON.

4) Start engine.

5) Read data of engine coolant temperature sensor signal using Subaru Select Monitor or OBD-II general scan tool.

NOTE:
- Subaru Select Monitor.
For detailed operation procedure, refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE".
- OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.


CHECK: Is the value less than -40°C (-40°F)?

YES: Go to step 1012.

NO: Repair poor contact.

NOTE:
In this case, repair the following:
- Poor contact in engine coolant temperature sensor
- Poor contact in ECM
- Poor contact in coupling connector (B22)

1012: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.

2) Remove air intake duct and air intake chamber assembly as a unit.





3) Remove engine harness connector bracket from cylinder block.





4) Remove blow-by hoses.





5) Disconnect connector from engine coolant temperature sensor.

Connector & Terminal (E9) No.1 (+) - Engine Ground (-):





6) Measure voltage between engine coolant temperature sensor connector and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Repair battery short circuit in harness between ECM and engine coolant temperature sensor connector.

NO: Go to step 1013.

1013: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to ON.

Connector & Terminal (E9) No.1 (+) - Engine Ground (-):





2) Measure voltage between engine coolant temperature sensor connector and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Repair battery short circuit in harness between ECM and engine coolant temperature sensor connector.

NO: Go to step 1014.

1014: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.

Connector & Terminal (E9) No.1 (+) - Engine Ground (-):





Measure voltage between engine coolant temperature sensor connector and engine ground.

CHECK: Is the voltage more than 4 V?

YES: Go to step 1015.

NO: Repair harness and connector.

NOTE:
In this case, repair the following:
- Open circuit in harness between ECM and engine coolant temperature sensor connector
- Poor contact in engine coolant temperature sensor connector
- Poor contact in ECM connector
- Poor contact in coupling connector (B22)

1015: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1) Turn ignition switch to OFF.

Connector & Terminal (E9) No.2 - Engine Ground:





2) Measure resistance of harness between engine coolant temperature sensor connector and engine ground.

CHECK: Is the resistance less than 5 Ohms.

YES: Replace engine coolant temperature sensor.

NO: Repair harness and connector.

NOTE:
In this case, repair the following:
- Open circuit in harness between ECM and engine coolant temperature sensor connector
- Poor contact in engine coolant temperature sensor connector
- Poor contact in ECM connector
- Poor contact in coupling connector (B22)