P0117

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. Clear Memory Mode




WIRING DIAGRAM

10I1: CHECK CURRENT DATA.
1. Start engine.
2. 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". Refer to Normal Scan Data Values.
- 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 (B21).
- Poor contact in joint connector (B122).

10I2: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from engine coolant temperature sensor.

Connector & Terminal (E8) No.1 (+) - Engine ground (-):

3. 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 10I3.

10I3: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1. Turn ignition switch to ON.

Connector & Terminal (E8) 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 10I4.

10I4: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.

Connector & Terminal (E8) 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 10I5.

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 (B21).
- Poor contact in joint connector (B122).

10I5: CHECK HARNESS BETWEEN ENGINE COOLANT TEMPERATURE SENSOR AND ECM CONNECTOR.
1. Turn ignition switch to OFF.

Connector & Terminal (E8) 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 (B21).
- Poor contact in joint connector (B122).