Hello Efrat,
Please note you need to pass some search criteria for the vehicle modules and this is mapped to R3 and defined in the CRM system tcode R3AC1 - adapter object overview for the object R3_VEHICLE. This setting is done under the "Filter Settings" tab for this object.
Otherwise, the module(VELO20_VEHICLE_CRM_EXTRACT and VELO13_SEARCH_VEHI_CORE) which searches for vehicles in the R3 system is unable to find any search criterion to return the data. Hence there is a stop status for the queue item.
So please ensure you have defined some criterion according to your business requirements.
Also for the completeness of the context request you to please go through the following documentation from VMS side, if you already haven't done so:
VMS documentation:
http://help.sap.com/erp2005_ehp_03/helpdata/EN/e3/ef683c2fe8ff6ee1000000 0a114084/frameset.htm
Hope the information helps.
Thanks,
Best regards,
Julin