A person who wants to tow a heavy luggage trailer with a category D coach must assess the vehicle combination separately. Under section 2(1) no. 14 FSG, category DE covers a category D towing vehicle with a trailer whose highest permissible maximum mass exceeds 750 kg, unless the vehicle approval provides otherwise.
Category DE therefore concerns the combination of the bus and the trailer. This article explains the 750 kg threshold, distinguishes DE from D and D1E and shows which entries in the driving licence, registration documents and approval records must be read together. The access requirements for category D and the 12,000 kg limit for C1E are separate questions.