In order to wake-p the transceiver remotely through the bus lines, a filter mechanism is integrated. This mechanism makes sure, that noise and ... (soll halt sicherung gegen fälschliches WakeUp sein).
Because of this mechanism it is not sufficient to simply pull the CANH or CANL bus lines to a dominant level for a certain time. To guarantee a successfull remote wake-up under all conditions, a message frames with a dominant phase of at least the maximum specified tcanh or tcanl in it is required.