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Test T: No Module/Network Communication - No Power To The Diagnostic Tool

PINPOINT TEST T: NO MODULE/NETWORK COMMUNICATION - NO POWER TO THE DIAGNOSTIC TOOL


T1-T3:






T4:






Normal Operation
Under normal operation the diagnostic tool is connected to the data link connector (DLC) C251 to communicate with the standard corporate protocol (SCP) communications network, universal asynchronous receiver-transmitter (UART)-based protocol (UBP) communications network, and the international standards organization (ISO) 9141 communications network. If communication cannot be established, the diagnostic tool and the DLC C251 must be checked for damage. If the diagnostic tool and the DLC C251 are OK, circuit 29-ED6 (OG/YE) must be checked for voltage and 31-ED6 (BK/YE), and 91-ED6 (BN) must be checked for an open condition.

Possible Causes
- fuse
- DLC C251
- diagnostic tool
- circuit 29-ED6 (OG/YE) open
- circuit 31-ED6 (BK/YE) open
- circuit 91-ED6 (BN) open