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Individual Flap Check

WARNING: This page is about a different car, the 1999 Mercedes-Benz CLK430, 1999 Mercedes-Benz CLK320, and 1998 Mercedes-Benz CLK320. However, it is still accessible from the selected car via links, so may be relevant.

Individual climate control vent flap operation can be checked using A/C push-button control unit. Temperature display areas will display test codes for each activated flap as well as flap position. To activate test, proceed as follows:

  1. Start and run engine at idle.
  2. Press left and right AUTO buttons.
  3. Set temperature to 72°F.
  4. Manually open center and side air outlets.
  5. Press REST and recirculated air button, and hold for more than 5 seconds.
  6. Left display area will display "0" and right display area will display "LO".
  7. Press left AUTO button to individually display stored test codes 0-15. See VENT FLAP TEST  table. Press right AUTO button to switch between HI or LO. When last flap position is indicated, first flap position will display.
  8. Press REST button to end individual test.

If system does not operate as specified in VENT FLAP TEST, perform VACUUM SYSTEM TESTS .

NOTE: Two-stage vacuum actuators function only at full stroke (100 percent) when long stroke (80 percent) and short stroke (20 percent) are pressed. Pressing short stroke (20 percent) by itself does not change flap position. Blower motor will be powered by 6 volts during test.
VENT FLAP TEST

A/C DISPLAYED Test Code Activated Flap (1) Test Condition Right Display Normal Operation/Air Output
0 All Press Right AUTO LO All Flaps Closed
Press Right AUTO HI All Flaps Open
01 Left Diverter Flap (2) Press Right AUTO LO Left Center Outlet Closed
Press Right AUTO HI Left Center Outlet Open, Cold Air
2 Right Diverter Flap (2) Press Right AUTO LO Right Center Outlet Closed
Press Right AUTO HI Right Center Outlet Open, Cold Air
3 Left Blend Air Flap (2) Press Right AUTO LO Left Center Outlet Closed
Press Right AUTO HI Left Center Outlet, Warm Air
4 Right Blend Air Flap (2) Press Right AUTO LO Right Center Outlet, Closed
Press Right AUTO HI Right Center Outlet, Warm Air
5 Left Defroster Flap Long Stroke (3) Press Right AUTO LO Side Defroster, Air Leak
Press Right AUTO HI Side Defroster, Maximum Air
6 Left Defroster Flap Long & Short Stroke (3) Press Right AUTO LO Left Defroster Outlet Closed
Press Right AUTO HI Left Defroster Outlet Open
7 Right Defroster Flap Long Stroke (1) Press Right AUTO LO Right Defroster Flap Open, Air Leak
Press Right AUTO HI Right Defroster Flap Open
8 Right Defroster Flap Long & Short Stroke (1) Press Right AUTO LO Right Defroster Flap Closed
Press Right AUTO HI Right Defroster Flap Open
9 Main Air Flap Long Stroke (4) Press Right AUTO LO Fresh Air
Press Right AUTO HI Recirculated Air 80%
10 Main Air Flap Long & Short Stroke (4) Press Right AUTO LO Fresh Air
Press Right AUTO HI Recirculated Air 100%
11 Left Footwell Flap Long Stroke (2) Press Right AUTO LO Left Footwell Flap Closed
Press Right AUTO HI Left Footwell Flap Open, Air Leak
12 Left Footwell Flap Long & Short Stroke (2) Press Right AUTO LO Left Footwell Flap, Air Leak
Press Right AUTO HI Left Footwell Flap Open
13 Right Footwell Flap Long Stroke (2) Press Right AUTO LO Right Footwell Flap Closed
Press Right AUTO HI Right Footwell Flap Open, Air Leak
14 Right Footwell Flap Long & Short Stroke (2) Press Right AUTO LO Right Footwell Flap, Air Leak
Press Right AUTO HI Right Footwell Flap Open
15 All Flaps Press Right AUTO LO All Flaps Closed
Press Right AUTO HI All Flaps Open
(1) Left defrost flap will also be activated (long and short stroke).
(2) Left and right defrost outlets will also be activated (long and short stroke).
(3) Right defrost flap will also be activated (long and short stroke).
(4) Left and right blend air flaps will also be activated.