This Preliminary Information communication provides information to the technician that some vehicles may have a high pitched whine noise from the vehicle noticed when driving in auto 4wd. When the transfer case control module has to move the transfer case actuator motor the higher current passing through the module causes an "electronic buzz or whine" within some of the capacitors in the module that can be heard by some of our customers. This can only be heard with all accessories and HVAC off and only when actuator movement is required. This does not indicate a concern with the module and should not be replaced to address this concern.
