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

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

D1-D3:

D4-D5:

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 audio control module, the satellite radio receiver (if equipped) and the instrument cluster. Voltage for the SJB is provided by circuits 905 (GY/LB), 1052 (TN/BK) and 1523 (DG). Both circuits 1205 (BK) provide ground.

DTC U0140 - sets when there is a loss of communication with the SJB

Possible Causes
- Fuse
- Circuit 905 (GY/LB) open
- Circuit 1052 (TN/BK) open
- Circuit 1205 (BK) open
- Circuit 1523 (DG) open
- Circuit 1847 (WH/OG) open (MS-CAN +)
- Circuit 1848 (PK/OG) open (MS-CAN -)
- SJB