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

PINPOINT TEST B: THE RESTRAINT CONTROL MODULE (RCM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


B1-B2:






Normal Operation
The RCM communicates with the diagnostic tool through the ISO 9141 communication network circuit 70 (LB/WH). If circuit 70 (LB/WH) becomes open or shorted to ground, communication to that module is not possible. Check circuit 70 (LB/WH) between the RCM C2041a and the data link connector (DLC) C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in the ISO 9141 communication network circuit, damage to the DLC C251, or damage to the RCM C2041a.

Possible Causes
- ISO 9141 communication network circuit 70 (LB/WH) open
- DLC C251
- RCM C2041a
- RCM