Subaru Crosstrek Service Manual: Dtc u0073 control module communication bus off

DTC DETECTING CONDITION:

Integrated unit communication is shut down because of high speed CAN error.

TROUBLE SYMPTOM:

CAN communication is not normal.

1.CHECK PERFORMING OF BASIC DIAGNOSTIC PROCEDURE.

Was the basic diagnostic procedure performed up to STEP 3?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF">Go to Step 2.

Perform the basic diagnostic procedure. Basic Diagnostic Procedure">

2.CHECK DTC.

1) Start the engine.

2) Using the Subaru Select Monitor, read DTC of CAN system. Read Diagnostic Trouble Code (DTC)">

Is U0073 a current malfunction?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF">Go to Step 3.

It may be a temporary poor contact. Perform the clear memory. Clear Memory Mode">

3.CHECK CAN COMMUNICATION CIRCUIT.

Check CAN communication circuit. CAN Communication Circuit Check > PROCEDURE">

Is CAN communication circuit faulty?

Repair the faulty portion, following the diagnosis procedure.

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF">Go to Step 4.

4.CHECK DTC.

1) Perform the inspection using the DTC check sheet. List of Diagnostic Trouble Code (DTC) > LIST">

2) Using the Subaru Select Monitor, read DTC of CAN system. Read Diagnostic Trouble Code (DTC)">

Is U0073 a current malfunction?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF">Go to Step 5.

System is normal.

5.CHECK CONTROL MODULE.

1) Turn the ignition switch to OFF.

2) Disconnect the control modules other than body integrated unit in order.

NOTE:

When disconnecting ECM or VDC CM, connect resistance of 120 ? between CAN Hi and CAN Lo as an alternative of end resistance.

3) Turn the ignition switch to ON.

4) Using the Subaru Select Monitor, read DTC of CAN system. Read Diagnostic Trouble Code (DTC)">

Is there any control module that U0073 is not detected as current malfunction?

Replace the control module.

Repeat 1) to 4) in step 3 until U0073 is not detected.

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