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P0108

G: DTC P0108 - PRESSURE SENSOR CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Immediately at fault recognition

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

10G1: CONNECT SUBARU SELECT MONITOR OR THE OBD-II GENERAL CAN 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 the OBD-II general scan tool switch to ON.

4) Start engine.

5) Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or OBD-II 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 more than 140 kPa (1050 mmHg, 41.34 inHg)?

YES: Go to step 10D10.

NO: Go to step 10D2.

10G2: CHECK INPUT SIGNAL FOR ECM.

Connector & Terminal (B136) No. 15 (+) - Chassis Ground (-):





Measure voltage between ECM connector and chassis ground.

YES: Is the voltage more than 4.5 V?

NO: Go to step 10G4.

NO: Go to step 10G3.

10G3: CHECK INPUT SIGNAL FOR ECM.

Connector & Terminal (B136) No.15 (+) - Chassis Ground (-):





Measure voltage between ECM connector and chassis ground.

CHECK: Does the voltage change more than 4.5 V by shaking harness and connector of ECM while monitoring the value with voltage meter?

YES: Repair poor contact in ECM connector.

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.

10G4: CHECK INPUT SIGNAL FOR ECM.

Connector & Terminal (B136) No.29 (+) - Chassis Ground (-):





Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage less than 0.2 V?

YES:
Go to step 10G6.

NO: Go to step 10G5.

10G5: CHECK INPUT SIGNAL FOR ECM. (USING SUBARU SELECT MONITOR.)

Read data of atmospheric absolute pressure signal using Subaru Select Monitor.

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.

CHECK: Does the value change more than 0 kPa (0 mmHg, 0 inHg) by shaking harness and connector of ECM while monitoring the value with Subaru select monitor?

YES:
Repair poor contact in ECM connector.

NO: Go to step 10G6.

10G6: CHECK HARNESS BETWEEN ECM AND PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.

2) Disconnect connector from pressure sensor.

3) Turn ignition switch to ON.

Connector & Terminal (E21) No.3 (+) - Engine Ground (-):





4) Measure voltage between pressure sensor connector and engine ground.

CHECK: Is the voltage more than 4.5 V?

YES: Go to step 10G7.

NO: Repair harness and connector.

NOTE: In this case repair the following.
- Open circuit in harness between ECM and pressure sensor connector.

10G7: CHECK HARNESS BETWEEN ECM AND PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF.

2) Disconnect connector from ECM.

Connector & Terminal (B136) No. 29 - (E21) No.2:





3) Measure resistance of harness between ECM and pressure sensor connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Go to step 10G8.

NO: Repair harness and connector.

NOTE: In this repair the following:
- Open circuit in harness between ECM and pressure sensor connector.

10G8: CHECK HARNESS BETWEEN ECM AND PRESSURE 8ENSOR CONNECTOR.

Connector & Terminal (B136) No. 16 - (E21) No. 1:





Measure resistance of harness between ECM and pressure sensor connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Go to step 10G9.

NO: Repair harness and connector.

NOTE: In this case, repair the following;
- Open circuit in harness between ECM and pressure sensor connector.

10G9: CHECK POOR CONTACT.
Check poor contact in pressure sensor connector.

CHECK: Is there poor contact in pressure sensor connector?

YES: Repair poor contact in pressure sensor connector.

NO: Replace pressure sensor.

10G10: CHECK HARNESS BETWEEN ECM AND PRESSURE SENSOR CONNECTOR.
1) Turn ignition switch to OFF and Subaru Select Monitor or the OBD-II general scan tool switch to OFF.

2) Disconnect connector from pressure sensor.

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

4) Read data of intake manifold absolute pressure 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 more than 140 kPa (1050 mmHg, 41.34 inHg)?

YES: Repair battery short circuit in harness between ECM and pressure sensor connector.

NO: Replace pressure sensor.