Test H: No Module/Network Communication

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

H1-H4:

Normal Operation
Under normal operation the diagnostic tool is connected to the data link connector (DLC) C251 to communicate with the controller area network (CAN), medium speed CAN, and international standards organization (ISO) 9141 communications networks. If communication can not be established, the diagnostic tool and the DLC C251 must be checked for damage. If the diagnostic tool and the DLC C251 are OK, ground circuits 570 (BK/WH), 875 (BK/LB) and voltage circuit 40 (LB/WH) must be checked for an open condition.

Possible Causes
- circuit 40 (LB/WH) open
- circuit 570 (BK) open
- circuit 875 (BK/LB) open
- DLC C251
- fuse
- diagnostic tool