Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding

PINPOINT TEST U: NO MEDIUM SPEED CONTROLLER AREA NETWORK (MS-CAN) COMMUNICATION, ALL MODULES ARE NOT RESPONDING

Normal Operation
The MS-CAN uses an unshielded twisted pair cable, circuits VDB06 (GY/OG) and VDB07 (VT/OG) provide the network connection to all modules on the network. The smart junction box (SJB), the instrument cluster (IC), the heating ventilation air conditioning (HVAC) module - electronic manual temperature control (EMTC) module (if equipped), the heating ventilation air conditioning (HVAC) module - electronic automatic temperature control (EATC) (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 audio rear control unit (RCU) (if equipped), the rear entertainment module (RETM) (if equipped), the power running board (PRB) module (if equipped), the parking aid module (PAM) (if equipped), the liftgate/trunk module (LTM), the driver seat module, and the dual climate control seat module (DCSM) (if equipped) all communicate with the scan tool using the MS-CAN.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- ACM
- RCU (if equipped)
- DCSM (if equipped)
- Driver seat module (DSM) (if equipped)
- RETM (if equipped)
- HVAC module - EATC (if equipped)
- HVAC module - EMTC (if equipped)
- IC
- PAM (if equipped)
- LTM (if equipped)
- PRB module (if equipped)
- SDARS module (if equipped)
- SJB
- DSP module (if equipped)

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