A/C Unit and Air Intake Housing Overview, Basis A/C System
A/C Unit and Air Intake Housing Overview, Basis A/C System
• Revised A/C units are being installed from MY 12 (use depends on the vehicle version) (A/C unit part number "8T_ 820 005"). With the introduction of these A/C units, other control motors are also being installed, which can be installed with both versions of the A/C units (interchanging is currently permitted). Refer to the Parts Catalog and the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
1 Air Intake Housing
• Removing and installing, refer to => [ A/C Unit Air Intake Housing ] A/C Unit Air Intake Housing.
• Disassembling and assembling, refer to => [ A/C Unit Air Intake Housing ] A/C Unit Air Intake Housing.
• There are different versions (with and without a connection for the glove compartment cooling).
• Connection for the glove compartment cooling on the air intake manifold, refer to => [ Glove Compartment Cooling to Air Intake Manifold Connection ] Glove Compartment Cooling to Air Intake Manifold Connection.
• From 01.2008, A/C units which have an additional connection for the glove compartment cooling are being installed. On vehicles without glove compartment cooling, this connection is sealed with a plug.
• From MY 12 (introduction depending on the vehicle version) a revised fresh air blower control module (J126) (and fresh air blower (V2) , Climatronic control module (J255) A/C control head and A/C units with part number"8T_ 820 005") are being used. The air intake manifold, along with the fresh air blower control module (J126) and the A/C unit is also revised. Be sure to use the correct version and allocation. Refer to the Parts Catalog and the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
2 A/C with Evaporator ("Basis" A/C system)
• May only be removed when refrigerant circuit has been discharged; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel.
• Evaporator, removing and installing with A/C Unit installed, from Start of Production through MY 12, refer to => [ Evaporator, A/C Unit Installed ] Evaporator, A/C Unit Installed.
• Revised A/C units and evaporators are being installed from MY 12 (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. See if the evaporator is available as an installation kit either without the evaporator housing or only together with the housing. Refer to the Parts Catalog. 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 ] Evaporator Housing.
• From the start of production through the MY 12 change-over, evaporators approximately 40 mm (1.6 in.) wide (block depth) are being installed (air conditioner part number "8K_ 820 005"). From MY 12, as a running change and depending on the version of the vehicle, an approximately 50 mm (2 in.) wide evaporator (block depth) is being installed (air conditioner part number "8T_ 820 005"). Pay attention to the correct allocation of the evaporator expansion valve (there are different versions). Refer to the Parts Catalog.
• Evaporator and evaporator housing, removing and installing, refer to => [ Evaporator Housing ] Evaporator Housing.
• A/C unit with evaporator, removing and installing, refer to => [ A/C Unit ] A/C Unit.
• Heating and A/C unit, disassembling and assembling, refer to => [ A/C Unit ] Overhaul.
• Clean air conditioning system evaporator with Ultrasound A/C Cleaner (VAS 6189A) => [ Evaporator Cleaning ] Evaporator Cleaning.
• Revised A/C units are being installed from MY 12 (use depends on the vehicle version) (A/C unit part number "8T_ 820 005"). With the introduction of these A/C units, other control motors are also being installed, which can be installed with both versions of the A/C units (interchanging is currently permitted). Refer to the Parts Catalog and Vehicle Diagnostic Tester in "Guided Fault Finding" function.
3 Recirculation Door Motor (V113)
• Removing and installing, refer to => [ Recirculation Door Motor (V113) ] Recirculation Door Motor (V113).
4 Airflow Door Motor (V71)
• Removing and installing, refer to => [ Air Flow Door Motor (V71) ] Air Flow Door Motor (V71).
5 Coolant Pipes To Heater Core
6 Expansion Valve
• Refrigerant lines with inner heat exchanger, disconnecting and reconnecting, refer to => [ Refrigerant Circuit Components ] Refrigerant Circuit Components.
• Removing and installing, refer to => [ Expansion Valve ] Expansion Valve.
• From the start of production through the MY 12 change-over, evaporators approximately 40 mm (1.6 in.) wide (block depth) are being installed (air conditioner part number "8K_ 820 005"). From MY 12, as a running change and depending on the version of the vehicle, an approximately 50 mm (2 in.) wide evaporator (block depth) is being installed (air conditioner part number "8T_ 820 005"). Pay attention to the correct allocation of the evaporator expansion valve (there are different versions). Refer to the Parts Catalog.
7 Grommet
• For sealing the opening through the plenum chamber rear wall for the refrigerant lines.
8 Cover For Refrigerant Pipes Leading To The Evaporator
• Removing and installing, refer to => [ Evaporator, A/C Unit Installed ] Evaporator, A/C Unit Installed.
9 Defroster Door Motor (V107)
• Removing and installing, refer to => [ Defroster Door Motor (V107) ] Defroster Door Motor (V107).
10 Footwell Door Motor (V261)
• Removing and installing, refer to => [ Footwell Door Motor (V261) and Left Footwell Door Motor (V108) ] Footwell Door Motor (V261) and Left Footwell Door Motor (V108).
• Retaining plate Footwell Door Motor (V261) removing and installing, refer to => [ Left Retaining Plate with Footwell Door Motor (V261) ] Left Retaining Plate With Footwell Door Motor (V261).
11 Left Condensation Water Drain Connection, (Driver Side)
• Condensation water drain valve, checking, removing and installing, refer to => [ Condensation Water Drain Hose ] Condensation Water Drain Hose.
12 Temperature Regulator Door Motor (V68)
• Removing and installing, refer to => [ Temperature Regulator Door Motor (V68) and Rear Temperature Door Motor (V137) ] Temperature Regulator Door Motor (V68) and Rear Temperature Door Motor (V137).
13 Footwell Outlet Temperature Sensor (G192)
• Removing and installing, refer to => [ Footwell Vent Temperature Sensor (G192)/Left Footwell Vent Temperature Sensor (G261) ] Footwell Vent Temperature Sensor (G192)/Left Footwell Vent Temperature Sensor (G261).
• The footwell vent temperature sensor is installed in the left footwell vent.
14 Center Outlet Temperature Sensor (G191)
• Removing and installing, refer to => [ Center Vent Temperature Sensor (G191) ] Center Vent Temperature Sensor (G191).
• The center outlet temperature sensor is installed in the center instrument panel air guide channel.
15 Connection to the A/C Control Head Climatronic Control Module (J255) on the A/C wiring harness.
16 Fresh Air Blower Control Module (J126)
• Removing and installing, refer to => [ Fresh Air Blower Control Module (J126) ] Fresh Air Blower Control Module (J126).
• Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• As a running change in MY 10, 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), Testing ] Testing and Inspection.
• Currently an auxiliary air heater heating element is installed for vehicles with a high voltage system (hybrid vehicles) and a gasoline engine. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• The activation of the electric auxiliary heater (the auxiliary heater heating element) occurs for vehicles with a gasoline engine from the Climatronic control module (J255) control head via the local Data bus (controlled using the same outlet and also using the fresh air blower control module (J126) ) on the auxiliary air heater control module (J604). Check the fresh air blower control module or the fresh air blower and also the auxiliary air heater control module when complaints arise for these vehicles. Refer to the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Make sure the auxiliary air heater heating element is working. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• From MY 12 (introduction depending on the vehicle version) a revised fresh air blower control module (J126) (and fresh air blower (V2) , Climatronic control module (J255) A/C control head and A/C units with part number"8T_ 820 005") are being used. The air intake manifold, along with the fresh air blower control module and the A/C unit is also revised. Be sure to use the correct version and allocation. Refer to the Parts Catalog and the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• The fresh air blower control module does not control the fresh air blower if the Climatronic control module allocation or adaptation to fresh air blower module (part number 8K0 820 521 or 8T0 820 521) is not according to the specification. There may not always be an entry in the DTC memory even though the activation of the fresh air blower is not OK. Make sure the Climatronic control module adaptation is correct. Refer to the Parts Catalog and to the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
17 Center Vent Adjustment Motor (V102)
• Removing and installing, refer to => [ Center Vent Adjustment Motor (V102) ] Center Vent Adjustment Motor (V102).
18 Right Condensation Water Drain Connection (Passenger Side)
• Condensation water drain valve, checking, removing and installing, refer to => [ Condensation Water Drain Hose ] Condensation Water Drain Hose.
19 Evaporator
• A/C unit with evaporator, removing and installing, refer to => [ A/C Unit ] A/C Unit.
• Evaporator, removing and installing with A/C Unit installed, from Start of Production through MY 12, refer to => [ Evaporator, A/C Unit Installed ] Evaporator, A/C Unit Installed.
• Revised A/C units and evaporators are being installed from MY 12 (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. See if the evaporator is available as an installation kit either without the evaporator housing or only together with the housing. Refer to the Parts Catalog. 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 ] Evaporator Housing.
• From the start of production through the MY 12 change-over, evaporators approximately 40 mm (1.6 in.) wide (block depth) are being installed (air conditioner part number "8K_ 820 005"). From MY 12, as a running change and depending on the version of the vehicle, an approximately 50 mm (2 in.) wide evaporator (block depth) is being installed (air conditioner part number "8T_ 820 005"). Pay attention to the correct allocation of the evaporator expansion valve (there are different versions). Refer to the Parts Catalog.
• Evaporator and evaporator housing, removing and installing, refer to => [ Evaporator Housing ] Evaporator Housing.
20 Heater Core for Heater Unit
• Heater core with the A/C installed, removing and installing, refer to => [ Heater Core/Housings ] Heater Core/Housings.
21 Auxiliary Air Heater Heating Element (Z35) / Honey Comb
• The auxiliary heater heating element is installed on vehicles with certain gasoline engines. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• Vehicles with gasoline engine, without auxiliary air heater heating element have a honey comb installed as a place holder (this assures that current conditions in the A/C with and without auxiliary air heater heating element are the same).
• Make sure the auxiliary air heater heating element is working. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• Auxiliary air heater heating element / honey comb with A/C system installed, removing and installing, refer to => [ Auxiliary Air Heater Heating Element (Z35)/Honey Comb ] Service and Repair.
• In MY 2009, as a running change, a new version of the auxiliary air heater heating element is being installed (the heating element is a bit more narrow); be sure to use the correct version and note the allocation. Refer to Electronic Parts Catalog (ETKA).
• As a running change in MY 10, gasoline engines that can run on bioethanol (Flex Fuel Vehicles) were introduced, which currently have an auxiliary air heater heating element. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• Currently an auxiliary air heater heating element is installed for vehicles with a high voltage system (hybrid vehicles) and a gasoline engine => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
22 Fresh Air Blower (V2)
• Removing and installing, refer to => [ Fresh Air Blower (V2) ] Service and Repair.
• Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Different versions. Refer to => [ Fresh Air Blower (V2) ] Service and Repair.
• As a running change in MY 10, 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), Testing ] Testing and Inspection.
• Currently an auxiliary air heater heating element is installed for vehicles with a high voltage system (hybrid vehicles) and a gasoline engine => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• The activation of the electric auxiliary heater (the auxiliary air heater heating element) occurs for vehicles with a gasoline engine from the Climatronic control module (J255) control head via the local Data bus (controlled using the same outlet and also using the fresh air blower control module (J126) ) on the auxiliary air heater heating element. Check the fresh air blower control module or the fresh air blower and also the auxiliary air heater control module (J604) when complaints arise for these vehicles. Refer to the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Make sure the auxiliary air heater heating element is working. Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection.
• From MY 12 (depending on the version of the vehicle) revised fresh air blower control module (J126) , fresh air blower (V2) , Climatronic control module (J255) A/C control head and A/C units with part number "8T_ 820 005" are being used. Be sure to use the correct version and allocation. Refer to the Parts Catalog and the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• The fresh air blower control module does not control the fresh air blower if the Climatronic control module allocation or adaptation to fresh air blower module (part number 8K0 820 521 or 8T0 820 521) is not according to the specification. There may not always be an entry in the DTC memory even though the activation of the fresh air blower is not OK. Make sure the Climatronic control module adaptation is correct. Refer to the Parts Catalog and to the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
23 Dust and Pollen Filter
• Removing and installing, refer to => [ Dust and Pollen Filter ] Service and Repair.
• Follow the replacement intervals.
• Different versions with and without activated charcoal filter element. Refer to => [ Dust and Pollen Filter with Activated Charcoal Insert ] Description and Operation and the Electronic Parts Catalog (ETKA).
24 Evaporator Vent Temperature Sensor (G263)
• Removing and installing, refer to => [ Evaporator Vent Temperature Sensor (G263) ] Evaporator Vent Temperature Sensor (G263).