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

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

Normal Operation
The SJB communicates with the scan tool through the medium speed controller area network (MS-CAN). Circuits VDB06 (GY/OG) (MS-CAN +) and VDB07 (VT/OG) (MS-CAN -) provide the network connection to the SJB. The SJB shares the MS-CAN network with the electronic automatic temperature control (EATC) or electronic manual temperature control (EMTC) module, the audio unit, the driver seat module (DSM), the digital versatile disc (DVD) player, the satellite radio receiver, the power liftgate module and the instrument cluster. Voltage for the SJB is provided by redundant circuits. Fuse 5 (10A) provides voltage, and circuit GD133 (BK) provides ground.

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

H1:

H1-H3:

H3-H4: