Incorporation of Front HVAC System Into Cooling Circuit

Incorporation of Front HVAC System into Cooling Circuit

Vehicles with a gasoline engine or with a 6 cylinder diesel engine with a specific Emissions Standard

• Starting with MY 2009, certain vehicles with a 6 cylinder TDI engine without an auxiliary heater, have an Auxiliary Air Heater Heating Element (Z35) installed depending on the emissions standard (running change depending on the engine). Refer to the Audi Sales Program.

• Auxiliary heater heating element (Z35) ) removing and installing refer to => [ Auxiliary Heater Heating Element ] Service and Repair, checking refer to => [ Auxiliary Heater Heating Element, Checking ] Testing and Inspection.

• Bleed cooling circuit, refer to => [ Coolant System, Bleeding ] Coolant System, Bleeding.






1 Coolant Supply From Engine

2 Coolant Return To Engine

3 Coolant Supply To Heater Core In Front Heating & A/C Unit

4 Coolant Return From Heater Core In Front Heating & A/C Unit

5 Heater Core In The Front A/C Unit

• Remove and install with the A/C unit installed, refer to => [ Heater Core, Heating & A/C Unit Installed ] Heater Core, Heating & A/C Unit Installed.

• Remove and install with the A/C unit removed, refer to => [ Heater Core, Heating & A/C Unit Removed ] Heater Core, Heating & A/C Unit Removed.

6 Coolant Hose and Coolant Pipe Group

• Installed under left front fender, refer to => [ Coolant Pump (V50) ] Coolant Pump (V50).

• There are different version depending on the engine and the vehicle equipment level.

7 Coolant Pump (V50)

• Not installed at this time on vehicles with 6 cylinder gasoline engine without parking heater optional equipment.

• In vehicles with 6 cylinder gasoline engine without parking heater optional equipment, Coolant Pump (V36) is installed in place of Coolant Pump (V50) , however it is not installed under the fender but is connected into engine cooling circuit.

• In vehicles with 6 cylinder gasoline engine and parking heater optional equipment, both pumps are currently installed ( Coolant Pump (V50) and Coolant Pump (V36) ).

• The Coolant Pump (V50) (and Coolant Pump (V36) ) is actuated independent of vehicle equipment by the respective Engine Control Module (ECM) and by the Climatronic Control Module (J255) (via various relays). Refer to and Vehicle Diagnosis, Testing and Information System VAS5051 in the "Guided Fault Finding" function.

• Coolant Pump (V50) , removing and installing, refer to => [ Coolant Pump (V50) ] Coolant Pump (V50).

8 Coolant Supply To Heater Core In Rear Heating & A/C Unit

• The rear A/C unit is optional equipment.

9 Coolant Return From Heater Core In Rear Heating & A/C Unit To Engine

• The rear A/C unit is optional equipment.

10 Heater Core In The Rear A/C Unit

• Remove and install with the A/C unit installed, refer to => [ Heater Core ] Heater Core.