Maintenance Vehicle Warning is a safety-related Cooperative Intelligent Transport System (C-ITS) service that mainly aims to reduce the number of accidents in connection to slow or stationary maintenance vehicles, e.g. mowing vehicles, vehicles for lane marking, road inspections or winter service vehicle.

Accidents often occur during bad weather and visibility conditions, whereby the visibility of slow or stationary maintenance vehicles on the hard shoulder or driving lanes is limited. A high risk of accidents occurs, especially on driving lanes, if the driving speed is excessively high in relation to the slow or stationary maintenance vehicle.
 
For the implementation of this service in Hessen, the maintenance vehicles will be equipped with the necessary technology (ETSI G5) for a vehicle-to-vehicle (V2V) communication to send appropriate messages and alert the drivers in advance. In Niedersachsen (Lower Saxony), in contrast, the MVW messages are triggered centralized by traffic management centers (TMC).