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

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

Normal Operation
The smart junction box (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 with the instrument cluster (IC), the accessory protocol interface module (APIM), the HVAC module (if equipped), the audio control module (ACM), the audio digital signal processing (DSP) module (if equipped), the satellite digital audio receiver system (SDARS) module (if equipped), the driver seat module (DSM) (if equipped), the dual climate control seat module (DCSM) (if equipped), the liftgate/trunk module (LTM) (if equipped), the parking aid module (PAM) (if equipped) and the rear entertainment module (RETM) (if equipped). Voltage for the SJB is provided by circuit CDC33 (VT/GN). Circuit GD133 (BK) provides ground.

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


I1-I2:






I3-I4: