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

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

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

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- SJB

D1:

D1-D2:

D3-D5: