Cabin Air Filter / Purifier: Service and Repair

Dust and Pollen Filter

• Dust and pollen filter change interval.

• The dust and pollen filter consists of 2 identical filter inserts. Pay attention to the correct position when installing (the filter air flow direction is marked with arrows).

• Clean the plenum chamber if necessary after replacing the dust and pollen filter; pay particular attention to the area under the air intake unit.

• Clean the dust and pollen filter installation shaft in the A/C unit before installing the new filter.

• Depending on the version, for some countries with high dust levels, a dust filter is installed at the air intake unit instead of intake air grille, which prevents dust and sand from entering the fresh air blower; replace this if necessary together with the dust and pollen filter => [ Fresh Air Intake Grille ] Fresh Air Intake Grille.

• There are different versions of the dust and pollen filter. The filters (with and without activated charcoal filter element) have different air resistance, so make sure it is the correct version. The control characteristic for activating the Fresh Air Blower (V2) is determined accordingly in the Climatronic Control Module (J255) A/C control head ("Basic" and "Comfort" versions).

• In model year 2008, vehicles with a "Comfort" A/C system will have a modified dust and pollen filter with an activated charcoal filter element installed as a running change. This filter with an improved interception rate for fine particulates has approximately the same air resistance values as the filter installed prior to the change, and for this reason will be installed in vehicles built up to the change.

- On vehicles with the Climatronic Control Module (J255) A/C control head "Basic" version, the filter without the activated charcoal filter element is installed. There is no Air Quality Sensor (G238) installed on these vehicles.

- On vehicles with the Climatronic Control Module (J255) A/C control head "Comfort" version, the filter with the activated charcoal filter element is installed. An Air Quality Sensor (G238) is installed on these vehicles.

Removing

• Depending on vehicle equipment, for certain versions or certain optional equipment (e.g. police or taxi vehicles equipped with "Global Positioning System"), it may be necessary to remove the glove compartment (it is possible other specific control modules must also be removed which are installed in this area, e.g. Special Purpose Vehicle Control Module (J608)).

• On vehicles with driving school equipment, pedals of driving school equipment must be removed if necessary (depending on version, service disconnect points are present on driving school pedals).

• Depending on vehicle equipment, a foam insulation element - A - may be installed (glued) in area of cover - B - on certain versions, remove it if necessary.





• In vehicles with right-hand steering, the dust and pollen filter is removed to the left from the A/C unit, in contrast to left-hand steering vehicles where it is removed to the right. The rest of the workflow is essentially the same.

- Remove cover - A - from the lower cover of the glove compartment - B -.





• The cover - A - is held in the lower cover of the glove compartment - B - by 4 catches. These catches could be difficult to loosen. Make sure not to damage the lower cover of the glove compartment - B - during removal.

- Cover the floor mat under the A/C unit dust and pollen filter shaft in the front passenger footwell with paper.

- Loosen the latch- B - and remove the dust and pollen filter cover - A - from the A/C unit.





- Remove the first section of the dust and pollen filter - A - from the A/C unit.





• Two identical filter elements are installed on top of each other in the A/C unit.

- Reach into the A/C unit shaft - C - and pull the second part of the filter - B - (at the tab) downward and then out of the A/C unit shaft.

Installing

- Clean the dust and pollen filter shaft of the A/C unit - C - of leaves, dust and other contaminants using a standard vacuum cleaner, Suction Nozzle (VAS 6288) (and hose attachment).





• Dust and other contaminants may be stuck on the A/C unit. To remove these contaminants, the Suction Nozzle (VAS 6288) includes a brush.

- Insert the first part of the dust and pollen filter - B - into the A/C unit shaft - C - and slide it to the top installation position. Note the flow direction (arrows on filter - D - point toward evaporator).

- If necessary, keep the first part of the dust and pollen filter - B - in its installation position e.g., with a steel ruler.

- Slide the second part of the dust and pollen filter - A - (under the first installed section - B -) into the A/C unit shaft. Note the flow direction (arrows on filter - D - point toward evaporator).

- Check the position of the seal - C - in the groove - D -.





- Install cover - A -, ensure proper fit in mount - E - and latch - B -

- Install the remaining removed components again in reverse order.