DTC P0107 Manifold Absolute Pressure/Barometric Pressure Sensor Circuit Low: Notes

DTC detecting condition:

Immediately at fault recognition

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Clear Memory Mode . and Inspection Mode Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Inspection Mode .
Use the check board when measuring the ECM terminal voltage and resistance.

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>Engine Electrical System>WIRING DIAGRAM .

Fig 1: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit Low - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

CHECK CURRENT DATA.
1. Start the engine.
2. Using the Subaru Select Monitor or a general scan tool, read the value of [Mani. Absolute Pressure].
  NOTE:
  - Subaru Select Monitor
    For detailed procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Subaru Select Monitor .
  - General scan tool
    For detailed operation procedures, refer to the general scan tool operation manual.
Is the value of [Mani. Absolute Pressure] less than 13.3 kPa (100 mmHg, 3.94 inHg)?
- Yes : Go to 2.
- No : Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis.
  NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
CHECK POWER SUPPLY OF MANIFOLD ABSOLUTE PRESSURE AND INTAKE AIR TEMPERATURE SENSOR.
1. Turn the ignition switch to OFF.
2. Disconnect the connector from the manifold absolute pressure and intake air temperature sensor.
3. Turn the ignition switch to ON.
4. Measure the voltage between the manifold absolute pressure and intake air temperature sensor connector and engine ground.
  Connector & terminal
  
  (E124) No. 4 (+) - Engine ground (-):
Is the voltage 4.5 V or more?
- Yes : Go to 3.
- No : repair the harness and connector.
  NOTE:
  In this case, repair the following item:
  - Open circuit in harness between ECM and the manifold absolute pressure and intake air temperature sensor connector
  - Poor contact of ECM connector
CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR.
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance of harness between ECM and the manifold absolute pressure and intake air temperature sensor connector.
  Connector & terminal
  
  (E158) No. 4 - (E124) No. 3:
Is the resistance less than 1 Ω?
- Yes : Go to 4.
- No : Repair the open circuit in harness between the manifold absolute pressure and intake air temperature sensor connector.
CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR.
Measure the resistance between ECM and engine ground.

Connector & terminal

(E158) No. 4 - Engine ground:

Is the resistance 1 MΩ or more?
- Yes : Go to 5.
- No : Repair the short circuit to ground in harness between ECM and manifold absolute pressure and intake air temperature sensor connector.
CHECK FOR POOR CONTACT.
Check for poor contact of ECM and manifold absolute pressure and intake air temperature sensor connector.

Is there poor contact of ECM or manifold absolute pressure and intake air temperature sensor connector?
- Yes : Repair the poor contact of ECM or manifold absolute pressure and intake air temperature sensor connector.
- No : Replace the manifold absolute pressure and intake air temperature sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>Manifold Absolute Pressure and Intake Air Temperature Sensor .