FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Test H: No International Standards Organization (ISO) 9141 Network Communication

PINPOINT TEST H: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 COMMUNICATIONS NETWORK COMMUNICATION


H1-H3:






H4-H6:






Normal Operation
The restraint control module (RCM) communicates with the diagnostic tool through the ISO 9141 communications network, circuit 70 (LB/WH). Check circuit 70 (LB/WH) between the RCM C310a and the data link connector (DLC) C251. The total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in the ISO 9141 communications network circuit, damage to the DLC C251, damage to the RCM C310a, or a problem in an in-line connector.

Possible Causes
- ISO 9141 communications network circuit 70 (LB/WH) open, short to ground, or short to voltage
- DLC C251
- RCM
- RCM C310a