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

DTC U1301 CAN-LS COUNTER ABNORMAL

DTC DETECTING CONDITION:

Communication is unstable because of low speed CAN communication error.

TROUBLE SYMPTOM:

Malfunction occurs in low speed CAN communication error counter.

WIRING DIAGRAM:

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1.CHECK DTC.

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

Are there DTC U1300 or U1302?

Perform the diagnosis according to DTC.

2.CHECK DTC.

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

Is U1301 current malfunction?

3.CHECK DTC.

1) Turn the ignition switch to OFF.

2) Disconnect all connectors (i84, i10, i88, i85 or i50, B419) that are connected to low speed CAN communication line.

3) Connect the disconnected connectors.

4) Turn the ignition switch to ON.

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

Is U1301 current malfunction?

4.CHECK HARNESS.

1) Turn the ignition switch to OFF.

2) Disconnect all connectors (i84, i10, i88, i85 or i50, B419) that are connected to low speed CAN communication line.

3) Using the tester, measure the resistance between terminals of harness.

Connector & terminal

(i84) No. 1 — (i10) No. 27 (combination meter):
(i84) No. 9 — (i10) No. 26 (combination meter):
(i84) No. 1 — (i88) No. 20 (A/C):
(i84) No. 9 — (i88) No. 19 (A/C):
(i84) No. 1 — (i85) No. 12 (audio):
(i84) No. 9 — (i85) No. 11 (audio):
(i84) No. 1 — (i50) No. 18 (navigation):
(i84) No. 9 — (i50) No. 6 (navigation):
(i84) No. 1 — (B419) No. 5 (gateway CM):
(i84) No. 9 — (B419) No. 4 (gateway CM):

Is the resistance less than 10 Ω?

Repair or replace the harness.

5.CHECK AUDIO OR NAVIGATION.

1) Connect the disconnected connectors.

2) Disconnect the connector of navigation (i85) or audio (i50).

3) Turn the ignition switch to ON.

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

Is U1301 current malfunction?

6.CHECK A/C CONTROL PANEL.

1) Turn the ignition switch to OFF.

2) Connect the audio or navigation module.

3) Disconnect the A/C control panel connector (i88).

4) Turn the ignition switch to ON.

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

Is U1301 current malfunction?

Replace the A/C control panel.

7.CHECK COMBINATION METER.

1) Turn the ignition switch to OFF.

2) Connect the disconnected connectors.

3) Perform the self-diagnosis of combination meter.

Is the self-diagnosis of combination meter OK?

Replace the combination meter.

8.CHECK BODY INTEGRATED UNIT.

1) Turn the ignition switch to OFF.

2) Disconnect all connectors (i84, i10, i88, i85 or i50, B419) that are connected to low speed CAN communication line.

3) Connect the disconnected connectors.

4) Turn the ignition switch to ON.

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

Is DTC U1301 a current malfunction?

Replace the body integrated unit.

9.CHECK HARNESS.

1) Turn the ignition switch to OFF.

2) Shake the harness used for low speed CAN communication circuit.

3) Turn the ignition switch to ON.

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

Is U1301 current malfunction?

Repair or replace the harness.

10.CHECK CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect all connectors (i84, i10, i88, i85 or i50, B419) that are connected to low speed CAN communication line.

Is there poor contact of connector terminal?

Repair the connector terminal, or replace harness.

Temporary poor contact occurs.