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

D1-D2:

D2-D3:

D4:

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 ABS module, the occupant classification sensor module, the restraints control module (RCM), the adaptive front lighting module (if equipped), the steering angle sensor module (if equipped) and the instrument cluster. Voltage is supplied by circuits CBP35 (YE/GY) and SBP11 (BU/RD). Ground is supplied by circuit GD140 (BK/GN).

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