On 20 July 2009, known locally as "Black Monday," the S-Bahn service was significantly reduced owing to safety checks on the trains ordered by the German Federal Railway Authority.
Pada 20 Juli 2009, penduduk lokal mengenalnya dengan "Minggu Gelap," layanan S-Bahn secara signifikan dikurangi karena pemeriksaan keselamatan pada kereta karena perintah dari Otoritas Kereta Api Federal Jerman.