Fresh Air Blower -V2-, REMOVING AND INSTALLING: Notes
The Fresh Air Blower -V2- as a replacement part is available in different versions. To ensure the correct allocation .
From 08/2007 as a running change, the Fresh Air Blower -V2- -A- is installed with an additional foam jacket -B- (as noise insulation) .
As a running change from MY 2009, a Fresh Air Blower -V2- -A- with a revised housing with an optimized motor with a suitable motor mount, is being installed. With the use of the revised Fresh Air Blower -V2-, the additional foam jacket on the housing -B- is discontinued because the larger motor mount has a new insulation mat (see -B- in the next illustration).
From MY 2012 (depending on the vehicle version), a revised Fresh Air Blower Control Module -J126-, Fresh Air Blower -V2-, Climatronic Control Module -J255- A/C display and control head and A/C units are gradually being used. Be sure to use the correct version and allocation using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
There is a label -A- on the outside of the A/C unit with a part number -B- that tells which version is installed.
The part number -B- on the label -A- can be read, for example, when the CD changer is removed (depending on the vehicle equipment level). Refer to DVD/CD Changer .
As a running change in MY 2010, gasoline engines that can run on bioethanol (Flex Fuel vehicles) were introduced, which currently have an Auxiliary Heater Heating Element -Z35-. Refer to Auxiliary Heater Heating Element -Z35-, CHECKING .
Currently an Auxiliary Heater Heating Element -Z35- is also installed on vehicles with a high voltage system (hybrid vehicles) and a gasoline engine. Refer to Auxiliary Heater Heating Element -Z35-, CHECKING .
For vehicles with a gasoline engine, the electric auxiliary heater (the Auxiliary Heater Heating Element -Z35-) is activated by the Climatronic Control Module -J255- display and control head via the local Data Bus (activated via the same outlet and also via the Fresh Air Blower Control Module -J126-) on the Auxiliary Air Heater Control Module -J604-. Also check the Auxiliary Air Heater Control Module -J604- if there is a concern about the Fresh Air Blower Control Module -J126- or the Fresh Air Blower -V2- for these vehicles using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function and refer to appropriate SYSTEM WIRING DIAGRAM.
From MY 2012 (use depends on the vehicle version), a revised Fresh Air Blower Control Module -J126- (and Fresh Air Blower -V2-, Climatronic Control Module -J255- A/C display and control head and A/C units with part number "8T_ 820 005") are gradually being used. The air intake housing, along with the Fresh Air Blower Control Module -J126- and the A/C unit was also revised. Be sure to use the correct version and allocation using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
If the allocation or adaptation of the Climatronic Control Module -J255- to the Fresh Air Blower Control Module -J126- (with the part number 8K0 820 521 or 8T0 820 521) is not according to the specification, then the Fresh Air Blower -V2- is not regulated by the Fresh Air Blower Control Module -J126-. There may not always be an entry in the DTC memory even though the activation of the Fresh Air Blower -V2- is not OK. Make sure the Climatronic Control Module -J255- is adapted correctly using the Vehicle Diagnostic Tester in the "Guided Fault Finding " function.
Check the Auxiliary Heater Heating Element -Z35- function. Refer to Auxiliary Heater Heating Element -Z35-, CHECKING .