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Test M

PINPOINT TEST M: NO MODULE/NETWORK COMMUNICATION - NO RESPONSE FROM THE DIAGNOSTIC TOOL


Test M1-M3:






Test M4:






Normal Operation
The data link connector (DLC) provides diagnostic tool access to the standard corporate protocol (SCP), controller area network (CAN) and the international standards organization (ISO) 9141 communications networks. Circuit 29-ED6 (OG/YE) provides voltage and circuits 31-ED6 (BK) and 91-ED6 (BN) supply the diagnostic tool ground.

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