Normal Operation
WARNING: This page is about a different car, the 2005 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
The 4WD control module communicates with the diagnostic tool through the high speed CAN communications network, circuits (W) and (B). If one of the bus wires becomes shorted to ground or voltage, communications can continue at a reduced level. Check circuits (W) and (B) between the 4WD control module 0318-01 and the DLC D-01. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the high speed CAN circuits, damage to the DLC D-01, damage to the 4WD control module 0318-01, or a problem in an in-line connector.