mercedes key remote central locking problem eis esl

i had this problem where my key remote for central locking did not always works. i noticed that my steering lock (esl ) not always was activated by the ignition switch (eis). this was on a sprinter 906 (euro model), but this will be helpfull to other models as well.
keywords; mercedes sprinter 906 central locking key remote eis esl intermittant problem