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Test E: The 4X4 Control Module Does Not Respond To The Scan Tool

PINPOINT TEST E: THE 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 PCM, the transmission control module (TCM) (if equipped), the ABS module, the restraints control module (RCM), the occupant classification system module (OCSM) and the instrument cluster (IC). Voltage is supplied by circuits CBP18 (GY/OG), SBB23 (RD/WH) and SBB26 (RD/BK). Ground is supplied by circuits GD138 (BK/WH) and GD145 (BK/BU).

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


E1-E2:






E3-E4: