Communication For Initializing Impossible

DIAGNOSIS:

Open or short circuit in data link connector

TROUBLE SYMPTOM:

Subaru Select Monitor communication failure

WIRING DIAGRAM:

Engine Electrical System <Ref. to WIRING DIAGRAM , Engine Electrical System.>

Fig 1: Data Link Connector Circuit Diagram

Courtesy of SUBARU OF AMERICA, INC.

Step	Check	Yes	No
1 CHECK POWER SUPPLY CIRCUIT. Connect DST-i or a general scan tool to the data link connector.	Is the DST-i or the general scan tool turned to ON?	Go to step 4.	Go to step 2.
2 CHECK POWER SUPPLY CIRCUIT. Measure the voltage between data link connector and chassis ground. Connector & terminal (B40) No. 16 (+) - Chassis ground (-):	Is the voltage 10 V or more?	Go to step 3.	Repair the power supply circuit. NOTE: In this case, repair the following item: Open or ground short circuit of harness between battery and data link connector Blown out of fuse (M/B No. 13)
3 CHECK HARNESS BETWEEN DATA LINK CONNECTOR AND CHASSIS GROUND. Turn the ignition switch to OFF. Measure the resistance of harness between data link connector and chassis ground. Connector & terminal (B40) No. 4 - Chassis ground: (B40) No. 5 - Chassis ground:	Is the resistance less than 5 Ω?	Repair the poor contact of data link connector.	Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit in harness between ECM connector and data link connector Open circuit of harness between ECM connector and engine ground Poor contact of ECM connector Poor contact of joint connector
4 CHECK HARNESS BETWEEN ECM AND DATA LINK CONNECTOR. Disconnect the connectors from ECM, DCCD CM, VDC CM, airbag CM, impact sensor, TPMS & keyless entry CM, and body integrated unit. CAUTION: When disconnecting the connector from airbag CM, always follow the precautions on AB section. <Ref. to CAUTION , General Description.> Measure the resistance of harness between ECM connector and data link connector. Connector & terminal (B135) No. 14 - (B40) No. 7:	Is the resistance less than 1 Ω?	Go to step 5.	Repair the open circuit of harness between ECM connector and data link connector.
5 CHECK HARNESS BETWEEN ECM AND DATA LINK CONNECTOR. Measure the resistance between data link connector and chassis ground. Connector & terminal (B40) No. 7 - Chassis ground:	Is the resistance 1 MΩ or more?	Repair the poor contact of ECM connector or data link connector.	Repair the short circuit to ground in harness between ECM connector and data link connector.