A Class 424 unit consists of four cars that share three jacobs bogies and can only be separated at maintenance facilities.

Different consists usually occur when the remains of partially destroyed units are combined to form one intact EMU.

The Class 424 vehicles were supposed to start operation in the year 2000, which was then delayed due to technical issues.

During large events such as the Hannover Messe, the fleet is often supported by Class 425 units from other regions.

The vehicles are modernized with new passenger information displays in the form of 8 double facing monitors throughout the interior.

As the vehicles have a floor height difference of about 80 centimeters to the Class 423 (to which platform heights were built for), the Class 424 trains are only operated outside the Stammstrecke as shuttle and complementary rush hour services between Dachau & Altomünster (S20) and Geltendorf/Buchenau & the main station (S4).

The 24 units for Cologne underwent a redesign process by internal DB workshops in Krefeld and Hanover as well as by Vossloh Rolling Stock in Kiel.

In December 2023, the modernization project received a special mention from the German Design Award 2024 in the category of "Aviation, Maritime and Railway".