Four-Wheel Drive (4WD) Control Module
WARNING: This page is about a different car, the 2006 Mercury Mountaineer and 2006 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
The 4WD control module (if equipped) uses the high speed CAN for communication with the diagnostic tool and other modules on the high speed CAN. The 4WD control module monitors and regulates the four wheel drive operation.
Check the high speed CAN circuits between the 4WD control module C281b and the DLC C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the high speed CAN, damage to the DLC C251, damage to the 4WD control module C281b, or a problem in an in-line connector.
For additional 4WD control module information, refer to FOUR WHEEL DRIVE (4WD) SYSTEMS .