ENGINE (DIAGNOSTICS)(H4DOTC DIESEL) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:

Immediately at fault recognition

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode and Inspection Mode .

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK CURRENT DATA.

1) Start the engine.

2) Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to “READ CURRENT DATA FOR ENGINE”.

• General scan tool

For detailed operation procedures, refer to the general scan tool operation manual.

Is the measured value 350 kPa (2,626 mmHg, 103 inHg)?

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 may be the cause.

2.CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and the manifold absolute pressure and intake air temperature sensor.

3) Measure the resistance of harness between ECM connector and the manifold absolute pressure and intake air temperature sensor connector.

Connector & terminal

(B134) No. 50 — (E124) No. 1:

(B135) No. 16 — (E124) No. 2:

Is the resistance less than 1 Ω?

Repair the harness and connector.

NOTE:

In this case, 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 coupling connector

3.CHECK HARNESS BETWEEN ECM AND MANIFOLD ABSOLUTE PRESSURE AND INTAKE AIR TEMPERATURE SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Start the engine.

3) Read the data of intake manifold absolute pressure signal using Subaru Select Monitor or general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to “READ CURRENT DATA FOR ENGINE”.

• General scan tool

For detailed operation procedures, refer to the general scan tool operation manual.

Is the measured value 350 kPa (2,626 mmHg, 103 inHg)?

Repair the short circuit to power in harness between ECM connector and the manifold absolute pressure and intake air temperature sensor connector.

4.CHECK POOR CONTACT.

Check for poor contact of the manifold absolute pressure and intake air temperature sensor connector.

Is there poor contact of the manifold absolute pressure and intake air temperature sensor connector?

Repair the poor contact of the manifold absolute pressure and intake air temperature sensor connector.

Replace the manifold absolute pressure and intake air temperature sensor.