When the first ICE 1 power cars were commissioned in late 1989, the intermediate cars were not yet available. Instead, they were coupled to retired couchette cars (type "yl") that were homologated for 200 km/h. These were fitted with special couplings for compatibility to the power cars. Usually, Class 110 locomotives served as "Angstlok" as well as for pulling the train on the return trip. For braking tests, the locos were sometimes coupled between two power cars, with match wagons on both sides. The test runs usually started at the Opladen repair workshop and used lines in the vicinity. Fast runs at up to 200 km/h were to Bielefeld and Bremen. Because of time pressure, some power cars were used for tests that had not yet been accepted by Bundesbahn. For longer test runs, two "dummy trainsets" comprising eleven couchette cars and ten InterCity cars (type "Bm 235") respectively were used to replace the missing intermediate cars.