d) As of 09/85

Air volume slide switch in position "min" fresh air/recirculated air flap closed - no fresh air supply

4th version with electro-pneumatic fresh/recirculated air switch (S24)

A Vacuum output
B Positive ventilation
E Vacuum input
S3 Air volume slide switch with vacuum switch
S24 Fresh/recirculated air switch
30 Vacuum connection on intake manifold
31 Check valve
33 2-stage vacuum element for fresh air/recirculated air flap
34 Evaporator housing
35 3-point vacuum distributor
a Connection to left-hand heater switch for vacuum water valve

Arrow, white Fresh air
Arrow, black Recirculated air







Air volume slide switch at 1st blower stage,fresh air/recirculated air flap open, 100% fresh air 4th version with electro-pneumatic fresh/recirculated air switch (S24)


A Vacuum output
B Positive ventilation
E Vacuum input
S3 Air volume slide switch with vacuum switch
S24 Fresh/recirculated air switch
30 Vacuum Connection on intake manifold
31 Check valve
33 2-stage vacuum element for fresh air/recirculated air flap
34 Evaporator housing
35 3-point vacuum distributor
a Connection to left-hand heater switch for vacuum water valve

Arrow, white Fresh air
Arrow, black Recirculated air







Air volume slide switch at 1st blower stage and fresh/recirculated air switch switched on, fresh air/recirculated air flap in position "recirculated air" corresponds to approx. 20% fresh air and 80% recirculated air

4th version with electro-pneumatic fresh/recirculated air switch (S24)

A Vacuum output
B Positive ventilation
E Vacuum input
S3 Air volume slide switch with vacuum switch
S24 Fresh/recirculated air switch
30 Vacuum Connection on intake manifold
31 Check valve
33 2-stage vacuum element for fresh air/recirculated air flap
34 Evaporator housing
35 3-point vacuum distributor
a Connection to left-hand heater switch for vacuum water valve