Defrost "a"

ACC Push-Button Control Panel:

Push-Button Control Panel

Vacuum Function "a" Defrost:

LEGEND
13 = Switchover valve for center nozzle flap
14 = Switchover valve for legroom flaps
15 = Switchover valve for defroster nozzle flaps
17 = Switchover valve for main air flap
18 = Switchover valve for fresh air/recirculating air flap
35 = Vacuum connection to vacuum line from vacuum pump
36 = Check valve
37 = Vacuum reservoir (not used on 123.1)
38 = 2-stage vacuum element for defroster nozzle flaps (flaps "open")
39 = Vacuum element for legroom flaps (flap "closed")
40 = Vacuum element for center nozzle flap (flap "closed")
41 = Vacuum element for fresh air/recirculating air flap (position "fresh air")
42 = Vacuum element for main air flap (flap "open")
44 = Throttle (orifice)
45 = Check valve (arrow = flow direction)
48 = 6-point distributor
49 = 4-point distributor
50 = 3-point distributor


Color Code
ge = Yellow
gn = Green
gr = Gray
rt = Red
ws = White
hbl = Light Blue
sw = Black