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

DTC P0193 FUEL RAIL PRESSURE SENSOR CIRCUIT HIGH

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 common rail 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 242 MPa (1,815,454 mmHg, 71,474 inHg) or more?

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 COMMON RAIL PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and the common rail pressure sensor.

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

Connector & terminal

(B134) No. 76 — (E126) No. 1:

(B134) No. 46 — (E126) No. 2:

Is the resistance less than 1 Ω?

Repair the harness and connector.

NOTE:

In this case, repair the following item:

• Open circuit in harness between ECM connector and common rail pressure sensor connector

• Poor contact of coupling connector

3.CHECK HARNESS BETWEEN ECM AND COMMON RAIL PRESSURE SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Start the engine.

3) Read the data of common rail 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 242 MPa (1,815,454 mmHg, 71,474 inHg) or more?

Repair the short circuit to power in harness between ECM connector and common rail pressure sensor connector.

4.CHECK POOR CONTACT.

Check for poor contact of common rail pressure sensor connector.

Is there poor contact of common rail pressure sensor connector?

Repair the poor contact of common rail pressure sensor connector.

Replace the common rail assembly.