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Test C: The Restraint Control Module (RCM) Does Not Respond to the Diagnostic Tool

PINPOINT TEST C: THE RESTRAINT CONTROL MODULE (ROM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


C1-C3:






Normal Operation
The RCM communicates with the diagnostic tool through the international standards organization (ISO) 9141 communications network circuit 70 (LB/WH). If circuit 70 (LB/WH) becomes open or shorted to ground communications to that module will not be possible. 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 circuit 70 (LB/WH), damage to the DLC C251, or damage to the C310a.

Possible Causes
- circuit 70 (LB/WH) open
- DLC C251
- RCM
- RCM C310a