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

DTC P1531 BATTERY CURRENT 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 “Battery current value” using the Subaru Select Monitor.

NOTE:

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

Is the data of “Battery current value” −100 A or less?

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.

2.CHECK HARNESS BETWEEN ECM AND BATTERY CURRENT SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the battery current sensor.

3) Start the engine.

4) Read the data of “Battery current value” using the Subaru Select Monitor.

NOTE:

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

Is the data of “Battery current value” −100 A or less?

Repair the short circuit to power in the harness between the ECM and battery current sensor connector.

3.CHECK HARNESS BETWEEN ECM AND BATTERY CURRENT SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance of the harness between the battery current sensor connector and engine ground.

Connector & terminal

(B538) No. 2 — Engine ground:

Is the resistance less than 5 Ω?

Repair the harness and connector.

NOTE:

In this case, repair the following item:

• Open circuit in harness between ECM and battery current sensor connector

• Poor contact of joint connector

4.CHECK FOR POOR CONTACT.

Check for poor contact of the battery current sensor connector.

Is there poor contact of the battery current sensor connector?

Repair the poor contact of the battery current sensor connector.

Replace the battery current sensor.