OVERVIEW - FRONT ACTUATORS, "Basis" VERSION

From 01/2008, A/C Units Which Have An Additional Connection For The Glove Compartment Cooling Are Being Installed As A Running Change. On Vehicles Without Glove Compartment Cooling, This Connection Is Sealed With A Plug.

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. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " function.

Revised A/C Units And Evaporators Are Gradually Being Installed From MY 2012 (Use Depends On The Vehicle Version) (A/C Unit Part Number "8T_ 820 005"). It Is Not Possible To Replace The Evaporator On This A/C Unit When The A/C Unit Is Installed. Before Working On The Evaporator, Check If It Is Available As An Installation Kit Either Without The Evaporator Housing Or Only Together With The Housing. If The Evaporator Is Available Only Together With The Housing, Then It Is Necessary To Remove The A/C Unit And Replace The Evaporator With The Evaporator Housing. Refer To EVAPORATOR HOUSING, REMOVING AND INSTALLING .

From the start of production up to the changeover from MY 2012, evaporators approximately 40 mm wide (block depth) were installed (A/C unit part number "8K_ 820 005"). From MY 2012 as a running change, an evaporator with an approximately 50 mm width (block depth) is being installed depending on the vehicle version (A/C unit part number "8T_ 820 005"). Pay attention to the correct allocation of the expansion valve to the evaporator (there are different versions).

For Refrigerant R1234yf, There Must Not Be Any Separable Connection Points In The Refrigerant Circuit In The Vehicle Interior (For Example, Separating Points On The Refrigerant Lines To The Evaporator). Therefore The A/C Unit (With The Evaporator Housing) Must Always Be Removed On These Vehicles And The Evaporator With The Refrigerant Lines Must Be Completely Replaced. Refer To The HEATER AND A/C UNIT, REMOVING AND INSTALLING .

Revised A/C units are gradually being installed from MY 2012 (use depends on the vehicle version) (A/C unit part number "8T_ 820 005"). With the introduction of these A/C units, other actuators are also being installed. The actuator different versions can currently be installed on both A/C unit versions (interchanging is currently permitted). Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " function.

From The Start Of Production Up To The Changeover From MY 2012, Evaporators Approximately 40 Mm Wide (Block Depth) Were Installed (A/C Unit Part Number "8K_ 820 005"). From MY 2012 As A Running Change, An Evaporator With An Approximately 50 Mm Width (Block Depth) Is Being Installed Depending On The Vehicle Version (A/C Unit Part Number "8T_ 820 005"). Pay Attention To The Correct Allocation Of The Expansion Valve To The Evaporator (There Are Different Versions).

There Are Different Versions Depending On The Refrigerant (R134a or R1234yf).

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. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " function. Refer to the appropriate Wiring Diagram.

Check The Auxiliary Heater Heating Element -Z35- function. Refer To AUXILIARY HEATER HEATING ELEMENT -Z35-, CHECKING .

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. Use 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. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " Function.

Revised A/C units and evaporators are gradually being installed from MY 2012 (use depends on the vehicle version) (A/C unit part number "8T_ 820 005"). It is not possible to replace the evaporator on this A/C unit when the A/C unit is installed. Before working on the evaporator, check if it is available as an installation kit either without the evaporator housing or only together with the housing. If the evaporator is available only together with the housing, then it is necessary to remove the A/C unit and replace the evaporator with the evaporator housing. Refer to EVAPORATOR HOUSING, REMOVING AND INSTALLING .

From the start of production up to the changeover from MY 2012, evaporators approximately 40 mm wide (block depth) were installed (A/C unit part number "8K_ 820 005"). From MY 2012 as a running change, an evaporator with an approximately 50 mm width (block depth) is being installed depending on the vehicle version (A/C unit part number "8T_ 820 005"). Pay attention to the correct allocation of the expansion valve to the evaporator (there are different versions).

For refrigerant R1234yf, There Must Not Be Any Separable Connection Points In The Refrigerant Circuit In The Vehicle Interior (For Example, Separating Points On The Refrigerant Lines To The Evaporator). Therefore The A/C Unit (With The Evaporator Housing) Must Always Be Removed On These Vehicles And The Evaporator With The Refrigerant Lines Must Be Completely Replaced. Refer To The HEATER AND A/C UNIT, REMOVING AND INSTALLING .

In MY 2009, As A Running Change, A New Version Of The Auxiliary Heater Heating Element -Z35- Is Being Installed (The Heating Elements Are A Bit More Narrow); Be Sure To Use The Correct Version And Note The Allocation.

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 .

There Are Different Versions. Refer to FRESH AIR BLOWER -V2-, REMOVING AND INSTALLING .

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. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " Function. Refer To The Appropriate Wiring Diagram.

Check the Auxiliary Heater Heating Element -Z35- function. Refer to AUXILIARY HEATER HEATING ELEMENT -Z35-, CHECKING .

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 with part number "8T_ 820 005" are gradually being used. Be sure to use the correct version and allocation. Use 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. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " function.