The invention relates to an exhaust gas aftertreatment device (1) of a motor vehicle, said device having a heater (2), which includes a plurality of heating elements (5, 6, 7), and a control unit (9) associated with the heater (2), wherein a common first switch (10) and in each case a second switch (32, 33, 34) are associated with the heating elements (5, 6, 7) and said heating elements (5, 6, 7) are jointly switchable by means of the first switch (10) and individually switchable by means of the second switches (32, 33, 34). The invention thereby provides that said first switch (10) is disposed separately from the control unit (9) and can be actuated by the same.