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

DTC U1303 WAKE-UP LINE ABNORMAL

DTC DETECTING CONDITION:

Open circuit or ground short of wake-up line

TROUBLE SYMPTOM:

Keyless access system operation may not be normal. (Only model with keyless access)

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK DTC.

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

Is U1303 a current malfunction?

2.CHECK DTC.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the body integrated unit and the gateway CM.

3) Connect the disconnected connectors.

4) Turn the ignition switch to ON and wait for at least 15 seconds.

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

Is U1303 a current malfunction?

3.CHECK HARNESS.

1) Turn the ignition switch to OFF.

2) Disconnect the body integrated unit connector.

3) Measure the voltage between body integrated unit terminal and chassis ground using tester.

Connector & terminal

(B281) No. 14 (+) — Chassis ground (−):

Is the voltage less than 1.5 V?

Replace the body integrated unit.

4.CHECK HARNESS.

1) Disconnect the connectors from the body integrated unit and the gateway CM.

2) Using the tester, check for open, short (power supply-output short, GND-output short) in the harness between terminals.

Connector & terminal

(B281) No. 14 — (B419) No. 15:

Is harness normal?

Replace the gateway CM.

Repair or replace the harness.

5.CHECK DTC.

1) Turn the ignition switch to OFF.

2) Close all doors and gate, and wait for one minute.

3) Turn the ignition switch to ON.

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

Is U1303 a current malfunction?

6.CHECK DTC.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the body integrated unit and the gateway CM.

3) Connect the disconnected connectors.

4) Turn the ignition switch to ON → OFF.

5) Close all doors and gate, and wait for one minute.

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

Is U1303 a current malfunction?

7.CHECK HARNESS.

Measure the voltage between body integrated unit terminal and chassis ground using tester.

Connector & terminal

(B281) No. 14 (+) — Chassis ground (−):

Is the voltage 8 V or more?

Replace the body integrated unit.

8.CHECK HARNESS.

1) Disconnect the gateway CM connector.

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

Connector & terminal

(B281) No. 14 (+) — Chassis ground (−):

Is the voltage 8 V or more?

Replace the body integrated unit.

9.CHECK CONNECTOR.

Check the connectors of the body integrated unit and the gateway CM.

Is there poor contact of connector?

Repair the poor contact of connector.

Temporary open, short, or poor contact occurred.