LAN SYSTEM (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC B1104 ACC POWER FAILURE

DTC DETECTING CONDITION:

Voltage malfunction caused by poor contact of ACC power supply circuit

TROUBLE SYMPTOM:

Does not exist.

NOTE:

B1104 may output when the ignition switch turns to ACC with the weak battery condition.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK DTC.

Read the DTC of body integrated unit using Subaru Select Monitor.

Is B1104 current malfunction?

2.CHECK DTC.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from body integrated unit and reconnect.

3) Turn the ignition switch to ACC.

4) Wait approx. 2 minutes.

5) Read the DTC of body integrated unit using Subaru Select Monitor.

Is B1104 current malfunction?

3.CHECK FUSE.

1) Turn the ignition switch to OFF.

2) Inspect the fuse.

Is fuse normal?

Replace the defective fuse.

4.CHECK HARNESS.

1) Disconnect the body integrated unit connector (B279).

2) Measure the voltage between body integrated unit connector and chassis ground using tester.

Connector & terminal

(B280) No. 7 (+) — Chassis ground (−):

Is the voltage 8.5 — 16.5 V?

Replace the body integrated unit.

Repair or replace the open or shorted circuit between body integrated unit and fuse.

5.CHECK CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the body integrated unit connector (B280).

Is there poor contact of connector?

Repair or replace the poor contact of connector.

A temporary change of voltage occurred.