Diagnostic Procedure for Subaru Select Monitor Communication: Inspection

Diagnosis: 

Subaru Select Monitor communication line is open or shorted.

Trouble symptom: 

Not communicable with Subaru Select Monitor.

Wiring diagram: 

CAN communication system Ref. to WIRING SYSTEM>CAN Communication System>WIRING DIAGRAM

• Engine type: FB

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• Engine type: FA

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1. CHECK SUBARU SELECT MONITOR 
   1. Connect the Subaru Select Monitor to another vehicle.
   2. Check communication condition between Subaru Select Monitor and vehicle.

   Is communication performed normally?

   Yes:  Go to  2

   No:  Subaru Select Monitor unit or diagnosis cable is faulty. Or check the fuse on the vehicle side.

2. CHECK DATA LINK CONNECTOR 

   Using a tester, measure the resistance of the ground circuit.

   Connector & terminal: Standard 

   (i221) No. 4 - Chassis ground: Less than 1 Ω

   (i221) No. 5 - Chassis ground: Less than 1 Ω

   Is the check result OK?

   Yes:  Go to  3

   No:  Repair or replace the open circuit.

3. CHECK DATA LINK CONNECTOR 
   1. Turn the ignition switch to ON.
   2. Using a tester, check the power supply of data link connector.

   Connector & terminal: Standard 

   (i221) No. 8 (+) - Chassis ground (-): 11 - 14 V

   (i221) No. 16 (+) - Chassis ground (-): 11 - 14 V

   Is the check result OK?

   Yes:  Go to  4

   No:  Check the power supply circuits to the data link connector.

4. CHECK COMMUNICATION FOR INITIALIZING ERROR 

   Perform the communication for initializing with each module by connecting the Subaru Select Monitor. (For systems whose module can communicate with diagnostic devices)

   NOTE: By performing [CAN bus connected ECU], confirmation of minimal connection modules is possible. Ref. to LAN SYSTEM (DIAGNOSTICS)>CAN bus check

   Is the communication possible with all modules?

   Yes:  The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

   No:  Perform the inspection using the check sheet of communication for initializing. Ref. to  COMMON (DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication>INSPECTION > CHECK USING THE NETWORK DIAGRAM (CHECK SHEET OF COMMUNICATION FOR INITIALIZING)

1. CHECK USING THE NETWORK DIAGRAM (CHECK SHEET OF COMMUNICATION FOR INITIALIZING) 

   Wiring diagram: 

   CAN communication system Ref. to WIRING SYSTEM>CAN Communication System>WIRING DIAGRAM

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   • DIAG-CAN, (H)_Advanced safety CAN, Camera local CAN, (G)_Chassis CAN

     Network diagram

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   • DIAG-CAN, Body CAN

     Network diagram

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   • DIAG-CAN, Power unit 1 CAN, (I)_Power unit 2 CAN, (J)_Exterior connection CAN, DCM local CAN

     Network diagram

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   1. MODULE INSTALLATION CHECK 
      1. Print the network diagram.
      2. Check the modules (modules which perform CAN communication) installed in the vehicle to be inspected, and draw double lines through the names of any modules that are not installed in the network diagram.
      NOTE: Make it possible to check the modules that are not installed.

      Was the module installation check above performed?

      Yes:  Go to  2

      No:  Perform the module installation check,  2

   2. SUBARU SELECT MONITOR COMMUNICATION INITIALIZATION CHECK 
      1. Connect the Subaru Select Monitor to the vehicle.
      2. Turn the ignition switch to ON.
      3. Check if communication with the module installed on the vehicle is possible.
      4. In the network diagram, write "◦" marks for the modules which succeeded in communication for initializing with Subaru Select Monitor. If the module failed in the communication, write a "" mark. Also write "◦" marks for the names of modules which do not communicate with Subaru Select Monitor (modules indicated by *1 in the network diagram).

      Are all modules that communicate with Subaru Select Monitor marked ""? (The communication was not possible between all the modules and the Subaru Select Monitor.)

      Yes:  Go to  3

      No:  Go to  6

   3. CHECK CENTRAL GATEWAY FUSE 
      1. Remove fuses No. 5, 9 and 38 from main fuse box.
      2. Check the fuse. Ref. to WIRING SYSTEM>CAN Communication System>WIRING DIAGRAM

      Is the check result OK?

      Yes:  Go to  4

      No:  Repair the defective part.

   4. CHECK CENTRAL GATEWAY POWER SUPPLY CIRCUIT 

      Using a tester, measure the voltage between the central gateway connector and chassis ground.

      Connector & terminal: Standard 

      (i88) No. 1 (+) - Chassis ground (-): 11 - 14 V

      (i88) No. 2 (+) - Chassis ground (-): 11 - 14 V

      (i88) No. 19 (+) - Chassis ground (-): 11 - 14 V

      Is the check result OK?

      Yes:  Go to  5

      No:  Repair the defective part.

   5. CHECK CENTRAL GATEWAY GROUND CIRCUIT 

      Using a tester, measure the resistance between the central gateway connector and chassis ground.

      Connector & terminal: Standard 

      (i88) No. 18 - Chassis ground: Less than 1 Ω

      (i88) No. 22 - Chassis ground: Less than 1 Ω

      Is the check result OK?

      Yes:  Replace the central gateway Control Module. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>Central Gateway Control Module

      No:  Repair the defective part.

   6. CHECK COMMUNICATION CIRCUIT 

      Check CAN communication circuit for the modules marked with "" in the network diagram as a result of step 2.

      NOTE:

      • When there is only one module where "" is marked, check the circuit with the closest number to the module where "" is marked.
      • When there are multiple modules where "" is marked, check the circuit on the upstream side which is closest to the branch leading to the modules where "" is marked. Ref. to LAN SYSTEM (DIAGNOSTICS)>CAN Communication Circuit Check

      Is the check result OK?

      Yes:  Go to  7

      No:  Repair the defective part.

   7. CHECK POWER SUPPLY CIRCUIT 

      Check power supply circuit of the control module that cannot perform communication. (Check the harness between control module connector and battery, and check the fuse.) Ref. to LAN SYSTEM (DIAGNOSTICS)>Control Module I/O Signal

      Is the check result OK?

      Yes:  Go to  8

      No:  Repair the defective part.

   8. CHECK GROUND CIRCUIT 

      Check ground circuit of the control module that cannot perform communication. Ref. to LAN SYSTEM (DIAGNOSTICS)>Control Module I/O Signal

      Is the check result OK?

      Yes:  The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

      No:  Repair the defective part.

2. EXAMPLE OF WRITING FOR THE CHECK SHEET OF COMMUNICATION FOR INITIALIZING 
   • DIAG-CAN, Body CAN

     -When communication with No. 16 in the network diagram is faulty (when there is only one module which cannot perform communication)

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     -When communication with No. 15 in the network diagram is faulty (when there are multiple modules which cannot perform communication)

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