Contact To ONSTAR (R) Call Center Is Impossible.

DEFINITION: When OnStar(R) call button is pressed, audio prompt "Connected to OnStar(R)" or "Impossible to connect to OnStar(R)" will be announced and connection is not performed.

Fig 1: Identifying Contact To OnStar(R) Call Center

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTICS CHART WITH TROUBLE CODE

Step	Check	Yes	No
1 CHECK FOR CONNECTION TO OnStar (R) Call Center. Turn ignition to ON (do not let the engine run). Press OnStar (R) button.	Is connection to OnStar (R) call center completed?	Repair temporary poor connection of wiring.	Go to step 2.
2 CHECK OnStar (R) SERIAL DATA RETURN CIRCUIT. Turn ignition switch to OFF. Disconnect connection from vehicle communication unit (VCU). Turn ignition switch to ON (do not let the engine run). Measure resistance between OnStar (R) serial data return circuit and ground. Connector & Terminal (i71) No. 9 (+) - Chassis ground (-):	Is the measured value approx. 5 V?	Go to step 3.	Go to step 6.
3 CHECK OnStar (R) SERIAL DATA (-) CIRCUIT. Measure voltage between OnStar (R) serial data (-) circuit and ground. Connector & Terminal (i71) No. 5 (+) - Chassis ground (-):	Is the measured value approx. 0.17 V?	Go to step 4.	Go to step 9.
4 CHECK CIRCUIT BETWEEN OnStar (R) SERIAL DATA (-) CIRCUIT AND TRANSCEIVER LOW REFERENCE CIRCUIT. Measure voltage between OnStar (R) serial data (-) circuit and transceiver low reference circuit. Connector & Terminal (i71) No. 5 (+) - (i71) No. 3 (-):	Is the measured value approx. 5 V?	Go to step 5.	Go to step 15.
5 CHECK OnStar (R) SERIAL DATA (+) CIRCUIT. Measure voltage between OnStar (R) serial data (+) circuit and ground. Connector & Terminal (i71) No. 4 (+) - Chassis ground (-):	Is the measured value approx. 0.17 V?	Go to step 18.	Go to step 12.
6 CHECK SERIAL DATA RETURN HARNESS. Turn ignition switch to OFF. Disconnect VIU connector. Disconnect VCU connector. Measure resistance between VIU connector and VCU connector. Connector & Terminal (i72) No. 27 - (i71) No. 9:	Is the measured value less than the 0.5 ohm?	Go to step 7.	Repair open harness.
7 CHECK SERIAL DATA RETURN HARNESS. Measure resistance between VIU connector and chassis ground. Connector & Terminal (i72) No. 27 - Chassis ground:	Is the measured value More than 1 Mohm?	Go to step 8.	Repair ground short of harness.
8 CHECK SERIAL DATA RETURN HARNESS. Turn the ignition switch to ON. Measure voltage between VIU connector and chassis ground. Connector & Terminal (i72) No. 27 (+) - Chassis ground (-):	Is the measured value less than 1 V?	Go to step 19.	Repair battery short of harness.
9 CHECK HARNESS (-). Turn ignition switch to OFF. Disconnect VIU connector. Disconnect VCU connector. Measure resistance between VIU connector and VCU connector. Connector & Terminal (i72) No. 28 - (i71) No. 5:	Is the measured value less than 0.5 ohm?	Go to step 10.	Repair open harness.
10 CHECK HARNESS (-). Measure resistance between VIU connector and chassis ground. Connector & Terminal (i72) No. 28 - Chassis ground:	Is the measured value More than 1 Mohm?	Go to step 11.	Repair ground short of harness.
11 CHECK HARNESS (-). Turn the ignition switch to ON. Measure voltage between VIU connector and chassis ground. Connector & Terminal (i72) No. 28 (+) - Chassis ground (-):	Is the measured value less than 1 V?	Go to step 19.	Repair battery short of harness.
12 CHECK SERIAL DATA (+) HARNESS. Turn ignition switch to OFF. Disconnect VIU connector. Disconnect VCU connector. Measure resistance between VIU connector and VCU connector. Connector & Terminal (i72) No. 29 - (i71) No. 4:	Is the measured value less than 0.5 ohm?	Go to step 13.	Repair open harness.
13 CHECK SERIAL DATA (+) HARNESS. Measure resistance between VIU connector and chassis ground. Connector & Terminal (i72) No. 29 - Chassis ground:	Is the measured value More than 1 Mohm?	Go to step 14.	Repair ground short of harness.
14 CHECK SERIAL DATA (+) HARNESS. Turn the ignition switch to ON. Measure voltage between VIU connector and chassis ground. Connector & Terminal (i72) No. 29 (+) - Chassis ground (-):	Is the measured value less than 1 V?	Go to step 19.	Repair battery short of harness.
15 CHECK TRANSCEIVER LOW REFERENCE HARNESS. Turn ignition switch to OFF. Disconnect VIU connector. Disconnect VCU connector. Measure resistance between VIU connector and VCU connector. Connector & Terminal (i72) No. 30 - 071) No. 3:	Is the measured value less than 0.5 ohm?	Go to step 16.	Repair open harness.
16 CHECK TRANSCEIVER LOW REFERENCE HARNESS. Measure resistance between VIU connector and chassis ground. Connector & Terminal (i72) No. 30 - Chassis ground:	Is the measured value More than 1 Mohm?	Go to step 17.	Repair ground short of harness.
17 CHECK TRANSCEIVER LOW REFERENCE HARNESS. Turn ignition switch to ON. Measure voltage between VIU connector and chassis ground. Connector & Terminal (i72) No. 30 (+) - Chassis ground (-):	Is the measured value less than 1 V?	Go to step 19.	Repair battery short of harness.
18 CHECK VCU HARNESS CONNECTOR. Check if there is any poor contact in VCU harness connector.	Is there any poor contact in connector?	Go to step 20.	Repair poor contact in connector.
19 CHECK VIU HARNESS CONNECTOR. Check if there is any poor contact in VIU harness connector.	Is there any poor contact in connector?	Go to step 21.	Repair poor contact in connector.
20 CHECK VCU. IMPORTANT: Perform OnStar (R) setup procedure. Replace VCU. < Ref. to REMOVAL , VEHICLE COMMUNICATION UNIT VCU. >	-	Go to step 22.	-
21 CHECK VIU. IMPORTANT: Perform OnStar (R) setup procedure. Replace VIU. < Ref. to REMOVAL , VEHICLE INTERFACE UNIT VIU. >	-	Go to step 22.	-
22 CHECK SYSTEM. Run the system and confirm the result of repair.	Was the trouble repaired?	System is OK.	Go to step 1.