A4 Mk3: Heating, ventilation, air conditioning system
Also for this vehicle: A4 Cabriolet L4-1.8L Turbo (AMB) (2005), A4 Cabriolet L4-2.0L Turbo (BWT) (2007), A4 Cabriolet Mk2, A4 Cabriolet V6-3.0L (AVK) (2003), A4 Mk1, A4 Mk2, A4 Quattro Cabriolet L4-2.0L Turbo (BWT) (2009), A4 Quattro Cabriolet V6-3.0L (BGN) (2005), A4 Quattro Cabriolet V6-3.2L (BKH) (2007), A4 Quattro Sedan L4-1.8L Turbo (AEB) (1998), A4 Quattro Sedan L4-1.8L Turbo (ATW) (2000), A4 Quattro Sedan L4-1.8L Turbo (AWM) (2001), A4 Quattro Sedan L4-2.0L Turbo (BPG) (2005), A4 Quattro Sedan L4-2.0L Turbo (CAEB) (2009), A4 Quattro Sedan V6-2.8L (ACK) (1997), A4 Quattro Sedan V6-3.0L (AVK) (2002), A4 Quattro Sedan V6-3.2L (BKH) (2005), A4 Quattro Wagon (8K5) L4-2.0L Turbo (CAEB) (2011), A4 Quattro Wagon L4-1.8L Turbo (AEB) (1999), A4 Quattro Wagon L4-1.8L Turbo (ATW) (2000), A4 Quattro Wagon L4-1.8L Turbo (AWM) (2001), A4 Quattro Wagon L4-2.0L Turbo (BPG) (2005), A4 Quattro Wagon L4-2.0L Turbo (CAEB) (2009), A4 Quattro Wagon V6-2.8L (AHA) (1998), A4 Quattro Wagon V6-3.0L (AVK) (2002), A4 Quattro Wagon V6-3.2L (BKH) (2005), A4 Sedan L4-1.8L Turbo (AEB) (1997), A4 Sedan L4-1.8L Turbo (ATW) (2000), A4 Sedan L4-1.8L Turbo (AWM) (2001), A4 Sedan L4-2.0L Turbo (BPG) (2005), A4 Sedan V6-2.8L (AFC) (1996), A4 Sedan V6-2.8L (AHA) (1998), A4 Sedan V6-3.0L (AVK) (2002), A4 Sedan V6-3.2L (BKH) (2007), A4 V6-3.0L (AVK) (2004).
Steering & suspension
Body & interior
Engine
Transmission
General
Heating & A/C
Choose Sections to see everything in a chapter, or a chapter title to start at its first page.
- 06Heating, ventilation, air conditioning systemHeating, ventilation, air conditioning system: Sections
Auxiliary heater › Aux. heater/heater booster79 pages
- Rules for cleanliness when working on auxiliary heater (and fuel system)
Safety precautions when working on vehicles fitted with auxiliary heater2 pages
- Notes on general repair work on vehicles fitted with auxiliary heater
Block diagram of components for auxiliary heater in vehicle5 pages
- Auxiliary heater remote control unit buttons and indicator lamp
- Checking and replacing batteries in auxiliary heater remote control (hand transmitter)
- Adaption of auxiliary heater remote control in supplementary heater control unit J364
- Activating and deactivating auxiliary heating/auxiliary ventilation by way of Multi Media Interface (MMI)
Diverting fuel for auxiliary heater13 pages
Diverting fuel (for auxiliary heater) from fuel tank3 pages
Checking fuel delivery rate of metering pump V545 pages
- Exploded view of metering pump V54
- Removing and installing metering pump V54
- Unfastening quick-release coupling at auxiliary heater fuel pipe
- Routing of fuel pipe to auxiliary heater
Checking CO2 content in exhaust gas of auxiliary heater3 pages
Incorporation of auxiliary heater into coolant circuit5 pages
Removing and installing auxiliary heater4 pages
Detaching and attaching auxiliary heater add-on components5 pages
Checking electrical components of auxiliary heater9 pages
- Checking actuation and electrical connections of auxiliary heater
- Preparation for checking auxiliary heater components
- Checking glow plug for heater Q9
- Checking combustion air blower V6
- Checking flame monitor G64
- Checking temperature sensor G18
- Checking supplementary and auxiliary heater temperature sensor 2 G587
- Checking fuel pre-heating heater element Z66
Functional description of auxiliary heater11 pages
Dismantling and assembling auxiliary heater11 pages
- Exploded view of auxiliary heater components
- Dismantling and assembling auxiliary heater
- Removing and installing temperature sensor G18
- Removing and installing supplementary and auxiliary heater temperature sensor 2 G587
- Removing and installing flame monitor G64
- Removing and installing glow plug for heater Q9
- Removing and installing fuel pre-heating heater element Z66
- Removing and installing combustion air blower V6
- Removing and installing burner element
- Removing and installing heat exchanger
Block diagram of auxiliary heater2 pages
Block diagram of auxiliary heater actuation with remote control2 pages
Air conditioner with refrigerant R134a › Air conditioner202 pages
Warning instructions when working on vehicles with high-voltage system3 pages
General information on air conditioning systems42 pages
- General notes
- Introduction
- Safety measures for vehicles with start/stop system
- Other reference material
Principles of air conditioning systems4 pages
- General work safety
- Product properties
- Handling refrigerant
- Handling pressure vessels
- Safety regulations for working with extraction and charging systems
- Safety measures for working on vehicles with air conditioning system and for handling refrigerant R134a
- Before using air conditioner after system has been re-charged
General information on refrigerant circuit47 pages
- Components of refrigerant circuit
Layout of components of refrigerant circuit and their influence on high-pressure and low-pressure sides16 pages
- Mechanically driven air conditioner compressor
- Electrically driven air conditioner compressor for vehicles with a high-voltage system
- Condenser
- Evaporator
- Reservoir
- Restrictor
- Receiver
- Expansion valve
- Expansion valve with refrigerant shut-off valve 2 for hybrid batteryN517
- Refrigerant shut-off valve 1 for hybrid batteryN516
- Refrigerant line with internal heat exchanger
- Quick-release couplings on refrigerant line
- O-rings
- Pipes and hoses of refrigerant circuit
- High-pressure safety valve
Design of refrigerant circuit3 pages
- Refrigerant circuit with electrically driven air conditioner compressor (with and without battery cooling module)
Connections for quick-release coupling in refrigerant circuit3 pages
Switches and senders in refrigerant circuit and related connections11 pages
- High-pressure switch for air conditioning systemF23
- High-pressure switch for magnetic clutchF118
- Low-pressure switch for air conditioning systemF73
- Connections with valve for refrigerant circuit switches
- Air conditioning system pressure switchF129
- High-pressure senderG65 and pressure sender for refrigerant circuitG805
- Refrigerant pressure and temperature senderG395
- Air conditioner compressor regulating valveN280
- Air conditioning system compressor speed senderG111
- Refrigerant temperature senderG454
Electrical components not installed in refrigerant circuit2 pages
Pressures and temperatures in refrigerant circuit3 pages
Tests and measurements performed with pressure gauge2 pages
Air conditioner service and recycling units3 pages
- Repair notes for refrigerant circuit
Laws and regulations4 pages
Refrigerant circuit22 pages
- Important repair notes for air conditioning systems
- Converting refrigerant circuits from refrigerant R12 to refrigerant R134a
Working with the air conditioner service station9 pages
- Important notes for working with the air conditioner service station
- Connecting air conditioner service station for measuring and testing
- Discharging refrigerant circuit with air conditioner service station
- Evacuating refrigerant circuit with air conditioner service station
- Charging refrigerant circuit with air conditioner service station
- Starting up air conditioner after charging
- Pouring refrigerant into reservoir (charging cylinder or storage vessel) of air conditioner service station
- Discharging air conditioner service station
Blowing out refrigerant circuit with compressed air and nitrogen2 pages
Flushing (cleaning) refrigerant circuit with refrigerant R134a4 pages
Tracing leaks in refrigerant circuit4 pages
Problems with refrigerant circuit4 pages
Connecting air conditioner service station6 pages
- Connecting air conditioner service station on vehicles with a connection on the low and high-pressure end of the refrigerant cir
Connecting air conditioner service station on vehicles with no connection on the low-pressure end of the refrigerant circuit4 pages
Checking pressures15 pages
Checking pressures in refrigerant circuit with air conditioner service station (with ignition switched off)4 pages
Checking pressures on vehicles with a restrictor and reservoir (with internally regulated air conditioner compressor)2 pages
Checking pressures on vehicles with an expansion valve and receiver (with internally regulated air conditioner compressor)2 pages
Checking pressures on vehicles with restrictor, reservoir and air conditioner compressor regulating valveN280 (with externally r2 pages
Checking pressures on vehicles with expansion valve, receiver and air conditioner compressor regulating valveN280 (with external2 pages
Checking pressures on vehicles with an electrically driven air conditioner compressor (vehicles with a high-voltage system)2 pages
Renewing components of refrigerant circuit8 pages
Renewing components7 pages
- Leaking or damaged components (except air conditioner compressor, reservoir or receiver)
- Leaking or damaged components (except air conditioner compressor, reservoir or receiver)
- Renewing air conditioner compressor without the need for refrigerant circuit cleaning
- Renewing air conditioner compressor on account of leakage or internal damage
- Renewing receiver or reservoir and restrictor after cleaning refrigerant circuit
- Renewing receiver or reservoir without the need for refrigerant circuit cleaning
- Renewing dryer cartridge/desiccant bag without the need for refrigerant circuit cleaning
Capacities for refrigerant R134a, refrigerant oil and approved refrigerant oils43 pages
Capacities for refrigerant R134a20 pages
- Capacities for Audi A1 (8X_) 2011 ?
- Capacities for Audi A2 (8Z_) 2001 ?
- Capacities for Audi A3 (8L_) 1997 ? and Audi TT (8N_) 1999 ?
- Capacities for Audi A3 (8P_) 2004 ?, Audi Q3 (8U_) 2012 ?
- Capacities for Audi TT (8J_) 2007 ?
- Capacities for Audi 80 (8A_/8C_), Audi Coupé (8B_), Audi Cabriolet (8G_) ? 2002
- Capacities for Audi A4 (8D_) 1995 ?
- Capacities for Audi A4 (8E_) 2001 ?, Audi A4 Cabriolet (8H_) 2003 ?
- Capacities for Audi A4 (8K_) 2008 ?, Audi A5 Coupé and Sportback (8T_) 2008 ?, Audi Q5 (8R_) 2008 ?, Audi A5 Cabriolet (8F_) 200
- Capacities for Audi 100 / Audi A6 (4A_) ? 1998
- Capacities for Audi A6 (4B_) 1998 ? and Audi allroad (4B_) ? 2005
- Capacities for Audi A6 (4F_) 2005 ?
- Capacities for Audi A6 (4G_) 2011 ?, Audi A7 (4G_) 2011 ?, Audi A6 hybrid (4G_) 2012 ?
- Capacities for Audi V8 (4C_) ? 1994
- Capacities for Audi A8 (4D_) 1994 ?
- Capacities for Audi A8 (4E_) 2003 ?
- Capacities for Audi A8 (4H_) 2010 ?, Audi A8 hybrid (4H_) 2012 ?
- Capacities for Audi Q7 (4L_) 2006 ?
- Capacities for Audi R8 (42_) 2008 ?
Approved refrigerant oils and refrigerant oil capacities22 pages
- Approved refrigerant oils
- Refrigerant oil capacities
- Capacities for Audi A1 (8X_) 2011 ?
- Capacities for Audi A2 (8Z_) 2001 ?
- Capacities for Audi A3 (8L_) 1997 ? and Audi TT (8N_) 1999 ?
- Capacities for Audi A3 (8P_) 2004 ?, Audi Q3 (8U_) 2012 ?
- Capacities for Audi TT (8J_) 2007 ?
- Capacities for Audi 80 (8A_/8C_), Audi Coupé (8B_), Audi Cabriolet (8G_) ? 2002
- Capacities for Audi A4 (8D_) 1995 ?
- Capacities for Audi A4 (8E_) 2001 ?, Audi A4 Cabriolet (8H_) 2003 ?
- Capacities for Audi A4 (8K_) 2008 ?, Audi A5 Coupé and Sportback (8T_) 2008 ?, Audi Q5 (8R_) 2008 ?, Audi A5 Cabriolet (8F_) 200
- Capacities for Audi 100 / Audi A6 (4A_) ? 1998
- Capacities for Audi A6 (4B_) 1998 ? and Audi allroad ? 2005
- Capacities for Audi A6 (4F_) 2005 ?
- Capacities for Audi A6 (4G_) 2011 ?, Audi A7 (4G_) 2011 ?, Audi A6 hybrid (4G_) 2012 ?
- Capacities for Audi V8 (4C_) ? 1994
- Capacities for Audi A8 (4D_) 1994 ?
- Capacities for Audi A8 (4E_) 2003 ?
- Capacities for Audi A8 (4H_) 2010 ?, Audi A8 hybrid (4H_) 2012 ?
- Capacities for Audi Q7 (4L_) 2006 ?
- Capacities for Audi R8 (42_) 2008 ?
Test equipment and tools8 pages
List of testers, tools and materials4 pages
- Tools and materials available from regional sales centre or importer
- Commercially available tools and materials
- Improvised tools
Air conditioning › Air conditioner182 pages
Safety precautions when working on vehicles fitted with an air conditioner and for handling refrigerant7 pages
Warning notices for working on vehicles with a high-voltage system3 pages
Notes on general repairs7 pages
- Contact corrosion
- Checking of electrical air conditioner components actuated or evaluated by way of other control units
Checking of electrical components actuated by the air conditioner3 pages
- Checking air conditioner components on vehicles with a high-voltage system
Servicing refrigerant circuit12 pages
- Block diagram of refrigerant circuit components (not for vehicles with a high-voltage system)
- Block diagram of refrigerant circuit components on vehicles with a high-voltage system
- Removing and installing refrigerant pressure and temperature senderG395, checking signal
- Checking pressure signal at refrigerant pressure and temperature senderG395
- O-rings for refrigerant circuit
Detaching mechanically driven air conditioner compressor from holder/attaching3 pages
- Detaching electrically driven air conditioner compressor from holder/attaching
Checking activation signal for air conditioner compressor regulating valveN2802 pages
Replacing air conditioner compressor pulley9 pages
- Preparation for pulley removal
- Replacing pulley (version without magnetic clutch)
Detaching pulley from air conditioner compressor/re-attaching2 pages
Replacing pulley with magnetic clutch N254 pages
Components for control and regulation of air conditioner not located in passenger compartment28 pages
Components not located in passenger compartment (all models)8 pages
- Components not located in passenger compartment, group of components "1"
- Position, actuation and operation of Climatronic coolant shut-off valveN422 and coolant shut-off valve
- Removing and installing ambient temperature sensorG17
- Components not located in passenger compartment, group of components "2"
- Components not located in passenger compartment, group of components "3"
- Coolant circulation pumpV50 (coolant pumpV36) on vehicles with a 4-cyl. engine
- Coolant circulation pumpV50 (coolant pumpV36) on vehicles with a 6-cyl. petrol engine
- Mode of operation of air quality sensorG238 and humidity sender in fresh air intake duct G657
Checking air quality sensorG238 / humidity sender in fresh air intake duct G6573 pages
- Removing and installing air quality sensorG238 / humidity sender in fresh air intake ductG657
- Checking, removing and installing passenger compartment forced air extractor
- Removing/installing, checking and cleaning plenum chamber water drain
- Checking, removing and installing fresh air intake
Components not located in passenger compartment on vehicles with a high-voltage system5 pages
- Components of battery cooling module
- Removing and installing temperature sensor -G756 upstream of evaporator and -G757 downstream of evaporator for hybrid battery
- Removing and installing battery fan 1V457
- Removing and installing control motor -V479- for air recirculation flap 1 and -V480- for air recirculation flap 2 for hybrid bat
- Moving battery cooling module to service position
- Checking, removing and installing battery cooling module condensation drain
Components for control and regulation of air conditioner located in passenger compartment18 pages
Components located in passenger compartment3 pages
- Removing and installing front left chest vent temperature sensorG385
- Removing and installing front right chest vent temperature sensorG386
- Removing and installing dash panel vents and rear vent
- Removing/installing and checking condensation drain hose
- Removing and installing sunlight penetration photosensorG107
Removing and installing air conditioner operating and display unit, Climatronic control unitJ2553 pages
- Removing and installing dash panel temperature sensor blowerV42
- Removing and installing dust and pollen filter
- Notes on dust and pollen filter with activated charcoal filter element
Cleaning air conditioner evaporator3 pages
Components of air conditioning unit and air intake box40 pages
- Components of air conditioning unit and air intake box with "Basic" type
- Components of air conditioning unit and air intake box with "Deluxe" type
- Block diagram of air conditioner control motors
- Connection for glove compartment cooling at air intake box
- Removing and installing air intake box of air conditioning unit
- Removing and installing right (front passenger side) footwell vent
- Removing and installing right footwell vent temperature senderG262
- Removing and installing evaporator output temperature senderG263
- Removing and installing centre vent temperature senderG191
- Removing and installing footwell vent temperature sender G192 / left footwell vent temperature sender G261
- Removing and installing left (driver side) footwell vent
- Dismantling and assembling air intake box of air conditioning unit
- Detaching air intake housing from air intake box
Removing and installing air flow flap control motorV712 pages
- Removing and installing air recirculation flap control motorV113
- Removing and installing temperature flap control motor V68 / rear temperature flap control motor V137
- Removing and installing fresh air blower control unitJ126
- Removing and installing fresh air blowerV2
- Removing and installing centre vent control motorV102
- Removing and installing right footwell flap control motorV109
- Removing and installing right centre vent control motorV111
- Removing and installing right mounting plate with control motors V109 and V111
- Dismantling and assembling right mounting plate with control motors V109 and V111
- Removing and installing right temperature flap control motorV159
- Removing and installing defroster flap control motorV107
- Removing and installing left centre vent control motorV110
- Removing and installing footwell flap control motorV261 / left footwell flap control motorV108
- Removing and installing left mounting plate with footwell flap control motorV261
- Dismantling and assembling left mounting plate with footwell flap control motorV261
- Removing and installing left mounting plate with control motors V108 and V110
- Dismantling and assembling left mounting plate with control motors V108 and V110
- Removing and installing left temperature flap control motorV158
- Removing and installing left heater housing (with temperature flaps)
Removing and installing right heater housing (with temperature flaps)3 pages
Removing and installing supplementary air heater elementZ35 / honeycomb element2 pages
Removing and installing heat exchanger of air conditioning unit3 pages
Block diagram of air distribution system14 pages
Air routing and air distribution in passenger compartment3 pages
Air intake, air outlet and air routing in air conditioning unit5 pages
- Block diagram of air ducts at battery cooling module
- Removing and installing rear exhaust air duct for drive batteryA2
- Removing and installing front exhaust air duct for drive batteryA2
- Removing and installing supply air duct for drive batteryA2
- Removing and installing left and right air ducts at drive batteryA2
Checking cooling output of air conditioner (not for vehicles with a high-voltage system)5 pages
Checking cooling output of air conditioner (vehicles with a high-voltage system only)5 pages
Checking heat output of air conditioner and actuation of temperature flaps5 pages
- Prerequisites for checking heat output and actuation of temperature flaps of air conditioner
Checking heat output and actuation of temperature flaps of air conditioner3 pages
Detaching refrigerant lines from air conditioner compressor/attaching5 pages
- Detaching refrigerant lines from air conditioner compressor/attaching (vehicles with 4-cyl. engine)
- Detaching refrigerant lines at air conditioner compressor/attaching (vehicles with 6-cyl. engine)
- Detaching refrigerant lines at air conditioner compressor/attaching (vehicles with 8-cyl. FSI engine)
- Starting up air conditioner after charging refrigerant circuit
Removing and installing air conditioner compressor15 pages
- Removing and installing mechanically driven air conditioner compressor (vehicles with 4-cyl. engine)
Removing and installing electrically driven air conditioner compressor (on vehicles with 4-cyl. engine)3 pages
- Removing and installing air conditioner compressor (vehicles with 6-cyl. TDI engine)
- Removing and installing air conditioner compressor (vehicles with 6-cyl. petrol engine)
- Removing and installing air conditioner compressor (vehicles with 8-cyl. FSI engine)
- Checking/replacing air conditioner compressor drive unit
- Unfastening and tightening air conditioner compressor drive shaft
- Removing and installing air conditioner compressor drive shaft
- Detaching drive plate with overload safeguard/attaching
- Checking concentricity of drive plate with overload safeguard/adjusting
- Unscrewing drive plate from air conditioner compressor/screwing on
- Removing and installing drive plate with rolling bearing
Dismantling and assembling air conditioning unit6 pages
- Dismantling and assembling air conditioning unit of "Basic" type
- Dismantling and assembling air conditioning unit of "Deluxe" type
- Levers and connecting elements at air conditioning unit
- "Deluxe" versions of air conditioning unit and air distribution housing
- Disassembling and assembling evaporator housing
- Capacities