Diagnostic Procedure For Subaru Select Monitor Communication: Inspection

Detecting condition: 

• Defective harness connector
• Defective AWD control module

Trouble symptom: 

Subaru Select Monitor communication failure

Wiring diagram: 

AWD control system Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>AWD CONTROL SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK IGNITION SWITCH  .

   Is the ignition switch ON?

   Yes:  Go to  2.

   No:  Turn the ignition switch to ON, and select the [AWD Control] using the Subaru Select Monitor.

2. CHECK BATTERY  .
   1. Turn the ignition switch to OFF.
   2. Measure the battery voltage.

   Is the voltage 10 V or more?

   Yes:  Go to  3.

   No:  Charge or replace the battery. Ref. to STARTING/CHARGING SYSTEMS (H4DO(HEV))>BATTERY .

3. CHECK BATTERY TERMINAL  .

   Is there poor contact at battery terminal?

   Yes:  Replace or tighten the battery terminal.

   No:  Go to  4.

4. CHECK INSTALLATION OF AWD CONTROL MODULE CONNECTOR  .

   Turn the ignition switch to OFF.

   Is the AWD control module connector inserted into the AWD control module until the clamp locks?

   Yes:  Go to  5.

   No:  Insert the AWD control module connector into the AWD control module.

5. CHECK LAN SYSTEM  .

   Check the LAN system. Ref. to LAN SYSTEM (DIAGNOSTICS) (HEV)>BASIC DIAGNOSTIC PROCEDURE .

   Is the check result OK?

   Yes:  Go to  6.

   No:  Perform the diagnosis for LAN system.

6. CHECK SUBARU SELECT MONITOR COMMUNICATION  .
   1. Turn the ignition switch to ON.
   2. Check whether communication with AWD can be executed normally.

   Is the [Select Function] screen displayed?

   Yes:  Check DTC of AWD control module. Ref. to AWD CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   No:  Go to  7.

7. CHECK POWER SUPPLY CIRCUIT  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the AWD control module connector.
   3. Turn the ignition switch to ON. (READY OFF)
   4. Measure the ignition power supply voltage between AWD control module connector and chassis ground.

   Connector and terminal 

   (B648) No. 21 (+) - Chassis ground (-):

   Is the voltage 10 V or more?

   Yes:  Go to  8.

   No:  Repair the open circuit of harness between AWD control module and battery.

8. CHECK GROUND CIRCUIT  .
   1. Turn the ignition switch to OFF.
   2. Measure the resistance of harness between AWD control module connector and chassis ground.

   Connector and terminal 

   (B648) No. 4 - Chassis ground:

   (B648) No. 17 - Chassis ground:

   Is the resistance less than 10 Ω?

   Yes:  Go to  9.

   No:  Repair the open circuit of the AWD control module ground circuit and poor contact of connector.

9. CHECK POOR CONTACT OF CONNECTOR  .

   Is there poor contact of control module power supply, ground circuit and data link connector?

   Yes:  Repair the connector.

   No:  Replace the AWD control module. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TH2A)>AWD CONTROL MODULE .