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

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

Normal Operation
The 4WD 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 4WD control module. The 4WD control module shares the HS-CAN network with the PCM, the power steering control module, the ABS module, the restraints control module (RCM), occupant classification sensor (OCS) module and the instrument cluster. Voltage for the 4WD control module is provided by circuit CBP34 (VT/BN) and SBP11 (BU/RD). Ground is provided by circuit GD148 (BK/YE).

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

D1-D2:

D3-D4: