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

1. -

DTC detecting condition:

Immediately at fault recognition

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

CHECK DATA MONITOR.
1. Start the engine.
2. Using the Subaru Select Monitor, read the value in [Mani. Absolute Pressure].
  NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .
Is the value of [Mani. Absolute Pressure] less than 13.3 kPa (100 mmHg, 3.93 inHg, 1.93 psi)?

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 again.

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 SENSOR.
1. Turn the ignition switch to OFF.
2. Disconnect the connector from manifold absolute pressure sensor.
3. Turn the ignition switch to ON.
4. Measure the voltage between manifold absolute pressure sensor connector and engine ground.
  Connector & terminal
  
  (E21) No. 3 (+) - Engine ground (-):
Is the voltage 4.5 V or more?

Yes: Go to 3.

No: Repair the following item.
- Open circuit of harness between ECM connector and the manifold absolute pressure and intake air temperature sensor connector
- Poor contact of ECM connector
CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR (OPEN).
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Measure the resistance of harness between ECM connector and manifold absolute pressure sensor connector.
  Connector & terminal
  
  (E158) No. 69 - (E21) No. 2:
Is the resistance less than 1 Ω?

Yes: Go to 4.

No: Repair the open circuit of the harness between the ECM connector and the manifold absolute pressure & intake air temperature sensor connector.
CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR (SHORT TO GROUND).
Measure the resistance between the ECM connector and engine ground.

Connector & terminal

(E158) No. 69 - Engine ground:

Is the resistance 1 MΩ or more?

Yes: Go to 5.

No: Repair short circuit to ground in harness between ECM connector and manifold absolute pressure sensor connector.
CHECK FOR POOR CONTACT.
Check for poor contact of ECM and manifold absolute pressure sensor connector.

Is there poor contact of ECM or manifold absolute pressure sensor connector?

Yes: Repair the poor contact of ECM or manifold absolute pressure sensor connector.

No: Replace the manifold absolute pressure sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>MANIFOLD ABSOLUTE PRESSURE SENSOR .