Diagnostic Procedure for Subaru Select Monitor Communication: Inspection

Detecting condition:

Defective harness
Power supply circuit malfunction
Defective seat position memory Control Module
Defective CAN communication circuit
Defective Subaru Select Monitor

Trouble symptom:

Not communicable with Subaru Select Monitor.

Wiring diagram:

Power seat system Ref. to WIRING SYSTEM>POWER SEAT SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to POWER SEAT MEMORY (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

CHECK OTHER COMMUNICATION .
Communicate with the system other than [Power Seat Memory] 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. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .
CHECK LAN SYSTEM .
Perform the inspection for LAN system. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

Is the check result OK?

Yes: Go to 3.

No: Perform the diagnosis according to the inspection for LAN system.
CHECK FOR POOR CONTACT .
1. Turn the ignition switch to OFF.
2. Disconnect the seat position memory Control Module connector.
3. Connect the disconnected connectors.
4. Turn the ignition switch to ON.
5. Communicate with [Power Seat Memory] 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: Go to 4.
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Disconnect the seat position memory Control Module connector.
3. Turn the ignition switch to ON.
4. Using a tester, measure the voltage between the seat position memory Control Module connector and chassis ground.
Connector & terminal

(St42) No. 24 (+) - Chassis ground (-):

(St42) No. 18 (+) - Chassis ground (-):

Is the voltage 9 - 16 V?

Yes: Go to 5.

No: Repair the open circuit of harness between the seat position memory Control Module connector and fuse.
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Using a tester, measure the resistance between the seat position memory Control Module connector and chassis ground.
Connector & terminal

(St43) No. 2 - Chassis ground:

(St42) No. 21 - Chassis ground:

Is the resistance less than 1 Ω?

Yes: Replace the seat position memory Control Module. Ref. to SEATS>POWER SEAT SYSTEM .

No: Repair the open circuit of harness between the seat position memory Control Module connector and chassis ground.