On the occasion of the International Transport Exhibition in Munich in 1965, the Deutsche Bundesbahn operated regular trains for the first time at speeds of up to 200 km/h. Subsequently, the four locomotives of the E 03 series were used for both test runs and for particularly fast TEE and F trains. With the delivery of the series locomotives of the 103.1 series, the prototype locomotives were increasingly assigned to testing duties. From the summer of 1974, all prototype 103 locomotives were based at the Hamburg-Eidelstedt depot. In addition to three express train pairs to Nuremberg and Munich, there were also local trains to Lüneburg, Hanover, Hildesheim, and Bremen on the schedule. Gradually, the long-distance services were phased out, although unscheduled express train operations did occur. In the autumn of 1979, the use of the 103.0 series in regular services came to an end, and all four locomotives were permanently assigned to the testing service of the Deutsche Bundesbahn. This model replicates the 103 002 as it was in service until September 1976. After that, it received UIC sockets on the front ends, hand grips, and ergonomic steps for boarding. A year later, single-arm pantographs were added, and in the autumn of 1980, the skirts under the buffer beams were finally removed. The model is excellently suited as a substitute for a standard series 103 for the 160 km/h express train "Hispania.".