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Test C: The Smart Junction Box (SJB) Does Not Respond to the Diagnostic Tool

PINPOINT TEST C: THE SMART JUNCTION BOX (SJB) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


C1-C2:






C3:






Normal Operation
The SJB communicates with the diagnostic tool through the medium speed controller area network (CAN), circuits 1827 (WH/LG) and 1828 (PK/LG). Check circuits 1827 (WH/LG) and 1828 (PK/LG) between the SJB C2280e and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the medium speed CAN circuits, damage to the DLC C251, damage to the SJB C2280e, or a problem in an in-line connector.

Possible Causes
- medium speed CAN circuit 1827 (WH/LG) open
- medium speed CAN circuit 1828 (PK/LG) open
- SJB
- SJB C2280e