Diagnostic Procedure For Subaru Select Monitor Communication: Inspection

Detecting condition: 

• Defective harness connector
• Power supply circuit malfunction
• Infotainment system module malfunction
• Defective CAN communication circuit
• Defective Subaru Select Monitor

Trouble symptom: 

Communication is impossible between the infotainment system module and Subaru Select Monitor.

Wiring diagram: 

Audio and navigation system Ref. to WIRING SYSTEM>AUDIO AND NAVIGATION SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK OTHER COMMUNICATION  .

   Communicate with the system other than the infotainment using the Subaru Select Monitor.

   Is the communication to other control module possible?

   Yes:  Go to  2 .

   No:  Perform the "Communication for Initializing Impossible" of LAN system.

2. CHECK LAN SYSTEM  .

   Inspect LAN system. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

   Is the check result OK?

   Yes:  Go to  3 .

   No:  Perform the inspection according to the diagnosis for LAN system.

3. CHECK FUSE  .

   Check the fuse of the infotainment. Ref. to ENTERTAINMENT AND MONITORING>RELAY AND FUSE>LOCATION .

   Is the check result OK?

   Yes:  Go to  4 .

   No:  Replace the fuse. If the replaced fuse blows out easily, repair the ground short circuit of the harness between the battery and audio connector, or between the navigation unit connectors.

4. CHECK HARNESS (POWER SUPPLY CIRCUIT)  .
   1. Turn off the audio or navigation unit.
   2. Turn the ignition switch to OFF.
   3. Disconnect the audio connector or navigation unit connector.
   4. Turn the ignition switch to ON.
   5. Using the tester, measure the voltage between audio connector or navigation unit connector and chassis ground.

      Connector and terminal 

      (i85) No. 3 (+) - Chassis ground (-):

      (i85) No. 4 (+) - Chassis ground (-):

   Is the voltage 10 - 13 V?

   Yes:  Go to  5 .

   No:  Repair the open circuit of harness between audio connector or navigation unit connector and fuse.

5. CHECK HARNESS (GROUND CIRCUIT)  .
   1. Turn the ignition switch to OFF.
   2. Using the tester, measure the resistance between audio connector or navigation unit connector and chassis ground.

      Connector and terminal 

      (i85) No. 7 - Chassis ground:

   Is the resistance less than 1 Ω?

   Yes:  Go to  6 .

   No:  Repair the open circuit of harness between audio connector or navigation unit connector and fuse.

6. CHECK INFOTAINMENT SYSTEM MODULE  .
   1. Connect the audio connector or navigation unit connector.
   2. Perform the communication with the infotainment system.

   Is communication possible?

   Yes:  It is possible that temporary poor communication occurs.

   No:  Replace the audio or navigation unit. Ref. to ENTERTAINMENT AND MONITORING>AUDIO . Ref. to ENTERTAINMENT AND MONITORING>NAVIGATION BODY .