The relay J36 controls the engagement circuit for the first additional heater coil O25A; the power supply for the relay arrives from the line for fuse F74 of the additional fuse box B98.The relay J37 controls the engagement circuit for the other additional heater coil O25B; the power supply for the relay arrives from the line for fuse F76 of the additional fuse box B98.The coils for relays J36 and J37 receive an ignition-controlled supply (INT) from the line for fuse F51 of the junction unit under the dashboard B2.The coil for relay J36 is energized by a signal from pin 8 of the climate control system control unit M70.The coil for relay J37 is energized by a signal for the engagement of the first resistance for O25B - from pin 7 of the climate control system control unit M70.