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Test F: The Four Wheel Drive (4X4) Control Module Does Not Respond To The Scan Tool

PINPOINT TEST F: THE FOUR WHEEL DRIVE (4X4) CONTROL MODULE DOES NOT RESPOND TO THE SCAN TOOL

Normal Operation
The 4X4 control module communicates with the scan tool through the high speed controller area network (HS-CAN). Circuits VDB04 (WH/BU) (HS-CAN +) and VDB05 (WH) (HS-CAN -) provide the network connection to the 4X4 control module. The 4X4 control module shares the HS-CAN with the PCM, the restraints control module (RCM), the occupant classification system module (OCSM), the instrument cluster (IC), and the SJB. Voltage is supplied by circuits SBB27 (BU/RD), SBP28 (GN/RD) and CBP10 (YE/OG). Ground is supplied by circuits GD161 (BK/YE) and GD174 (BK/WH).

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- 4X4 control module


F1-F2:






F3-F4: