Preparation for Test 1. Engine: At Idle 2. Press . 3. Press stage 4. 4. Set temperature selection to (simultaneously press and ) 6. Press for more than 6 seconds. 7. The display alternately shows the number and the in-car temperature. 8. Press within 5 seconds. The display shows . 9. By pressing the "air distribution" and 1 - 4 (one after the other) the individual vacuum actuators are activated (see table). Turn on: By pressing the individual button. Turn off: By pressing the same button again. Function indication: By LED in individual button. 10. Press to end test program. Note: Two stage vacuum actuators function at full stroke (100%) only, if the long stroke (80%) and the short stroke (20%) are pressed. Pressing the short stroke (20%) by itself does not change the flap position. If the number appears on the display and non of the buttons listed in the table are depressed, then there is no vacuum present and air comes from the defroster outlets and the side outlets.

Diagnostic Trouble Code (DTC)	Activated flap 3)	Test condition	Nominal value/Air output	Test step/Remedy 1)
	Defroster flap long stroke (80%)	Pushbutton stage 4	Leak air from defroster outlets, air venting from side outlets left/right.	23 25.0 32 1.0
	Defroster flap short stroke (20%)	Pushbutton 2)	Air venting from side outlets left/right.	23 26.0 32 2.0
	Center outlet tempering flap	Pushbutton stage 3	Warm air from center outlet.	23 20.0 32 3.0
	Center outlet diverter flap	Pushbutton	Cold air from center outlet.	23 19.0 32 4.0
	Recirculating air flap long stroke (80%)	Pushbutton stage 2	Air flow from center outlet increases.	23 21.0 32 5.0
	Recirculating air flap short stroke (20%)	Pushbutton 2)	100% recirculating air	23 22.0 32 6.0
	Footwell flap long stroke (80%)	Pushbutton stage 1	Air flow from footwell outlets increases.	23 23.0 32 7.0
	Footwell flap short stroke (20%)	Pushbutton 2)	Air flow from left/right footwell outlets.	23 24.0 32 8.0

1) Observe Preparation for Test. 2) Before actuating the short stroke (20%), the long stroke (80%) must be actuated. 3) All activations of the flaps also can be performed with the Hand-Held Tester (HHT).

Note:
1. Observe Preparation for Function Test, see 11 .
2. The components and functions described in the table below can be
activated via the Hand-Held Tester (HHT).
The data and notes for the individual test steps are to be taken
from the display in the window of the HHT.

	Possible cause	Test step/Remedy 1)
	Auxiliary fan (M4)	23 11.0 , 12.0
	Auxiliary coolant pump (M13)	23 14.0
	Duovalve (Y21)	23 15.0
	A/C compressor (A9)	23 17.0
	Defroster outlet flap	23 25.0 , 26.0 , 32 1.0 , 2.0
	Footwell flap	23 23.0 , 24.0 , 32 7.0 , 8.0
	Fresh/recirculating air flap	23 21.0 , 22.0 , 32 5.0 , 6.0
	Diverter/tempering flaps	23 19.0 , 20.0 , 32 3.0 , 4.0
	Blower motor (A32m1)	23 16.0
Gasoline engines only	Closed throttle speed increase	23 13.0

1) Observe Preparation for Test, see 22 .