Fig. 10.30. External view of the front passenger footwell with the mat removed: 1 – body bottom; 2 – seat belt tensioner system control unit; 3 – seat heating system relay
The seat heating is switched on by a switch on the center console next to the gearshift lever. Voltage from fuse #10 is supplied to the heating elements via relay 3 (fig. 10.30). The relay is located in the front passenger footwell under the carpet. When the first heating level is switched on, one 20 W control lamp lights up. When the heating level increases, two 60 W lamps light up. When the heating is switched on at low power, alternating voltage is supplied (the time in the on state is about 30%).
Material borrowed from an online resource www.mercedesman.ru