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Communication For Initializing Impossible

DETECTING CONDITION:

Defective harness connector

TROUBLE SYMPTOM:

Communication is impossible between VDC and Subaru Select Monitor.

WIRING DIAGRAM:

Fig 1: Communication For Initializing Impossible - Wiring Diagram

G05020297

DIAGNOSIS PROCEDURE

Step	Check	Yes	No
1 CHECK IGNITION SWITCH.	Is the ignition switch ON?	Go to step 2.	Turn the ignition switch to ON, and select VDC mode using Subaru Select Monitor.
2 CHECK BATTERY. Turn the ignition switch to OFF. Measure the battery voltage.	Is the voltage more than 11 V?	Go to step 3.	Charge or replace the battery.
3 CHECK BATTERY TERMINAL.	Is there poor contact at battery terminal?	Repair or tighten the battery terminal.	Go to step 4.
4 CHECK SUBARU SELECT MONITOR COMMUNICATION. Turn the ignition switch to ON. Using the Subaru Select Monitor, check whether communication to other system can be executed normally.	Are the system name and model year displayed on Subaru Select Monitor?	Go to step 8.	Go to step 5.
5 CHECK SUBARU SELECT MONITOR COMMUNICATION. Turn the ignition switch to OFF. Disconnect the VDCCM&H/U connector. Turn the ignition switch to ON. Check whether communication to other systems can be executed normally.	Are the system name and model year displayed on Subaru Select Monitor?	Replace the VDCCM&H/U. < Ref. to VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM&H/U) . >	Go to step 6.
6 CHECK HARNESS CONNECTOR BETWEEN EACH CONTROL MODULE AND DATA LINK CONNECTOR. Turn the ignition switch to OFF. Disconnect the VDCCM&H/U, ECM and TCM. Measure the resistance between data link connector and chassis ground. Connector & terminal (B40) No. 10 - Chassis ground:	Is the resistance more than 1 MΩ?	Go to step 7.	Repair the harness and connector between each control module and data link connector.
7 CHECK THE VDCCM&H/U OUTPUT SIGNALS. Turn the ignition switch to ON. Measure the voltage between data link connector and chassis ground. Connector & terminal (B40) No. 10 (+) - Chassis ground (-):	Is the voltage less than 1 V?	Go to step 8.	Repair the harness and connector between each control module and data link connector.
8 CHECK THE HARNESS CONNECTOR BETWEEN VDCCM&H/U AND DATA LINK CONNECTOR. Measure the resistance between VDCCM&H/U connector and data link connector. Connector & terminal (B310) No. 26 - (B40) No. 10:	Is the resistance less than 0.5 Ω?	Go to step 9.	Repair harness and connector between VDCCM&H/U and data link connector.
9 CHECK INSTALLATION OF VDCCM&H/U CONNECTOR. Turn the ignition switch to OFF.	Is the VDCCM&H/U connector inserted into VDCCM&H/U until the clamp locks onto it?	Go to step 10 .	Insert VDCCM&H/U connector into VDCCM&H/U.
10 CHECK POWER SUPPLY CIRCUIT. Turn the ignition switch to ON. (engine OFF) Measure the ignition power supply voltage between VDCCM&H/U connector and chassis ground. Connector & terminal (B310) No. 14 (+) - Chassis ground (-):	Is the voltage 10 - 15 V?	Go to step 11 .	Repair open circuit in harness between VDCCM&H/U and battery.
11 CHECK THE HARNESS CONNECTOR BETWEEN VDCCM&H/U AND CHASSIS GROUND. Turn the ignition switch to OFF. Disconnect the connector from the VDCCM&H/U. Measure the resistance of harness between VDCCM&H/U connector and chassis ground. Connector & terminal (B310) No. 6 - Chassis ground:	Is the resistance less than 0.5 Ω?	Go to step 12 .	Repair the open circuit in harness between VDCCM&H/U and inhibitor side connector, and poor contact of coupling connector.
12 CHECK POOR CONTACT IN CONNECTOR.	Is there poor contact in control module power supply, ground circuit and data link connector?	Repair the connector.	Replace the VDCCM&H/U. < Ref. to VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM&H/U) . >