What problem does DIC Message service 4 Wheel Drive mean?

There are many things that could cause that message. Its a generic message to indicate something in the 4WD system has malfunctioned. It could be the transfer case actuator and/or position sensor, it could be the front axle engagement actuator or even something as simple as the selector switch. In order to narrow down the possibilities, it will need to be hooked up to a diagnostic computer, so the fault codes can be retrieved from the Transfer Case Control Module (ATC).