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Test E: The Smart Junction Box (SJB) Does Not Respond To The Scan Tool

PINPOINT TEST E: THE SMART JUNCTION BOX (SJB) DOES NOT RESPOND TO THE SCAN TOOL


E1-E2:






E3-E4:






Normal Operation
The SJB communicates with the scan tool through the medium speed controller area network (MS-CAN). Circuits 1847 (WH/OG) (MS-CAN +) and 1848 (PK/OG) (MS-CAN -) provide the network connection to the SJB. The SJB shares the MS-CAN network with the instrument cluster. Ground is provided by circuit 570 (BK/WH).

DTC U0073 (SJB) - sets when the MS-CAN bus performance is compromised.

Possible Causes
- Fuse
- Circuit 570 (BK/WH) open
- Circuit 1847 (WH/OG) open (MS-CAN +)
- Circuit 1848 (PK/OG) open (MS-CAN -)
- SJB