Diagnostic Procedure For Subaru Select Monitor Communication: Inspection

Trouble symptom: 

Communication is impossible with Subaru Select Monitor.

Detecting condition: 

• Defective harness
• Power supply circuit malfunction
• Power rear gate control module malfunctioning
• Body integrated unit malfunctioning
• Defective CAN communication circuit
• Defective Subaru Select Monitor

Wiring diagram: 

Power rear gate system Ref. to WIRING SYSTEM>POWER REAR GATE SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK FUSE  .
   1. Turn the ignition switch to OFF.
   2. Check the fuse.

   Is the check result OK?

   Yes:  Go to  2 .

   No:  Replace the fuse. If the replaced fuse blows out easily, repair the ground short circuit in the harness between the battery and Power rear gate control module.

2. CHECK POWER SUPPLY CIRCUIT (OPEN)  .
   1. Disconnect the Power rear gate control module connector in the order of (L85) → (L84).
   2. Turn the ignition switch to ON.
   3. Using a tester, measure the voltage between Power rear gate control module connector and chassis ground.

      Connector and terminal 

      (L84) No. 16 (+) - Chassis ground (-):

      (L85) No. 6 (+) - Chassis ground (-):

   Is the voltage 10 V or more?

   Yes:  Go to  3 .

   No:  Repair the open circuit of the harness between Power rear gate control module connector and the fuse.

3. CHECK GROUND CIRCUIT (OPEN)  .
   1. Turn the ignition switch to OFF.
   2. Using a tester, measure the resistance between Power rear gate control module connector and chassis ground.

      Connector and terminal 

      (L85) No. 4 - Chassis ground:

   Is the resistance less than 1 Ω?

   Yes:  Go to  4 .

   No:  Repair the open circuit in harness between Power rear gate control module connector and chassis ground.

4. CHECK BODY INTEGRATED UNIT  .

   Check the body control system. Ref. to BODY CONTROL (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

   Is the check result OK?

   Yes:  Go to  5 .

   No:  Perform the inspection according to the diagnosis for body control system.

5. CHECK SUBARU SELECT MONITOR  .
   1. Connect the Subaru Select Monitor to another vehicle.
   2. Check whether the communication for initializing can be executed normally.

   Is communication normal?

   Yes:  Go to  6 .

   No:  Repair or replace the Subaru Select Monitor.

6. CHECK Power rear gate control module  .
   1. Connect the Power rear gate control module connector in the order of (L84) → (L85).
   2. Communicate with [Power Rear Gate] using the Subaru Select Monitor.

   Is communication possible?

   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:  Replace Power rear gate control module. Ref. to POWER REAR GATE SYSTEM>POWER REAR GATE CONTROL MODULE .