Diagnostic Procedure for Subaru Select Monitor Communication: Inspection

Trouble symptom: 

Cannot communicate with [Driver Monitor].

Detecting condition: 

• Defective harness connector
• Power supply circuit malfunction
• Driver Monitoring Unit malfunctioning
• Defective CAN communication circuit
• Defective Subaru Select Monitor

Wiring diagram: 

• Driver monitoring system Refer to WIRING SYSTEM>Driver Monitoring System>WIRING DIAGRAM .
• CAN communication system Refer to WIRING SYSTEM>CAN Communication System>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK IGNITION SWITCH  .

   Check the ignition switch. Is the ignition switch ON?

   Yes  : Go to  2.

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

2. CHECK BATTERY  .
   1. Turn the ignition switch to OFF.
   2. Check the battery. Refer to STARTING/CHARGING SYSTEMS (H4DOTC)>Battery>INSPECTION . Refer to STARTING/CHARGING SYSTEMS (H4DO)>Battery>INSPECTION .

   Is the check result OK?

   Yes  : Go to  3.

   No  : Charge or replace the battery.

3. CHECK INSTALLATION OF Driver Monitoring Unit CONNECTOR  .

   Check the Driver Monitoring Unit connector.

   Is the Driver Monitoring Unit connector inserted into the Driver Monitoring Unit until it locks?

   Yes  : Go to  4.

   No  : Insert the Driver Monitoring Unit connector into the Driver Monitoring Unit until it is locked.

4. CHECK LAN SYSTEM  .

   Perform the diagnosis for LAN system. Refer to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

   Is there any fault in LAN system?

   Yes  : Perform the inspection according to the diagnosis for LAN system.

   No  : Go to  5.

5. CHECK SUBARU SELECT MONITOR COMMUNICATION  .
   1. Turn the ignition switch to ON.
   2. Check whether communication to the Driver Monitoring Unit can be executed normally.

   Is communication with [Driver Monitor] possible?

   Yes  : Read the DTC of [Driver Monitor] using the Subaru Select Monitor. Refer to DRIVER MONITOR (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   No  : Go to  6.

6. CHECK SUBARU SELECT MONITOR  .

   Connect the Subaru Select Monitor to another vehicle to verify that the communication for initializing can be executed normally.

   Is communication for initializing possible?

   Yes  : Go to  7.

   No  : Repair or replace the Subaru Select Monitor.

7. CHECK Driver Monitoring Unit POWER SUPPLY CIRCUIT (OPEN SHORT CIRCUIT)  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the Driver Monitoring Unit connector.
   3. Using a tester, measure the voltage between Driver Monitoring Unit connector and chassis ground.

      Connector & terminal 

      (i87) No. 8 (+) - Chassis ground (-):

   Is the voltage 10 - 15 V?

   Yes  : Go to  8.

   No  : Repair the open or short circuit of harness or the poor contact of connector between the Driver Monitoring Unit connector and the battery.

8. CHECK Driver Monitoring Unit GROUND CIRCUIT (OPEN)  .
   1. Turn the ignition switch to OFF.
   2. Measure the resistance between Driver Monitoring Unit connector and chassis ground.

      Connector & terminal 

      (i87) No. 6 - Chassis ground:

   Is the resistance less than 10 Ω?

   Yes  : Go to  9.

   No  : Repair the open circuit of Driver Monitoring Unit ground circuit or poor contact of connector.

9. CHECK POOR CONTACT OF CONNECTOR  .

   Check Driver Monitoring Unit power supply, ground circuit and data link connector for poor contact.

   Is there poor contact?

   Yes  : Repair the poor contact.

   No  : Replace Driver Monitoring Unit. Refer to INSTRUMENTATION/DRIVER INFO>DRIVER MONITORING UNIT .