A4 Cabriolet Mk2: 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 V6-3.0L (AVK) (2003), A4 Mk1, A4 Mk2, A4 Mk3, 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 heater218 pages
Self diagnosis, V.A.G Inspection Service112 pages
Auxiliary heater self-diagnosis8 pages
- Function
- Fault recognition
- Guided fault-finding
- Technical data of self-diagnosis
- Test requirements for self-diagnosis
- Safety precautions
Self-diagnosis procedure5 pages
Connecting up vehicle diagnostic, testing and information system VAS 5051A and selecting functions4 pages
- Interrogating fault memory
Auxiliary heater fault table3 pages
Auxiliary heater final control diagnosis3 pages
Basic setting of auxiliary heater6 pages
Basic setting of auxiliary heater (activation and deactivation)5 pages
Reading measured value block27 pages
Starting reading measured value block3 pages
Display groups "001” to "005”8 pages
Display groups as of "006”14 pages
- Display group "006”
- Table of activation and deactivation conditions for "Supplementary heating” function of auxiliary heater
- Display group "007”
- Display group "008”
- Display group "009”
- Display group "010”
- Display group "011”
- Table of shutoff criteria for auxiliary heater/"supplementary heating” function
- Display groups "012” to "014”
- Display group "015”
- Display group "081”
- Display group "125”
- Display group "126”
- Display groups currently not used for service purposes
Adaption of auxiliary heater17 pages
Entering undervoltage shutoff value (adaption channel "01”)5 pages
Remote control adaption procedure (adaption channel "04”)3 pages
Chassis number adaption procedure (adaption channel "81”)3 pages
Adaption procedure in adaption channels "03”, "05” and "06” (and "87”)3 pages
Auxiliary heater electrical checks19 pages
Preparation for electrical checks4 pages
Electrical checks at vehicle electrical system connector6 pages
Electrical checks at connector to auxiliary heater components8 pages
Functional description of auxiliary heater10 pages
Auxiliary heater control sequence7 pages
- Auxiliary heater components
- Control sequence on start-up of auxiliary heater (also as supplementary heater)
- Control sequence at low ambient temperatures
- Control sequence at ambient temperatures greater than 0 °C or after starting engine
- Auxiliary heater control curve
- Heater coolant shut-off valve N279 actuation
Checking convenience data bus system7 pages
- Function of data bus systems
Checking convenience data bus system5 pages
Aux. heater/heater booster106 pages
Servicing auxiliary heater4 pages
- Safety precautions when working on vehicles fitted with auxiliary heater
- Notes on general repair work on vehicles fitted with auxiliary heater
- Rules for cleanliness when working on auxiliary heater and fuel system
Layout of components for auxiliary heater in vehicle11 pages
Removing and installing heater coolant shut-off valve N2794 pages
- Auxiliary heater remote control buttons and indicator lamp
- Checking and replacing batteries in auxiliary heater remote control
- Adaption of auxiliary heater remote control hand transmitter in auxiliary heater control unit J364
Activating and deactivating auxiliary heating/auxiliary ventilation by way of control unit in dash panel insert J2853 pages
Diverting fuel for auxiliary heater16 pages
Diverting fuel (for auxiliary heater) from fuel tank5 pages
- Front-wheel drive vehicles up to 01.03 (gradual conversion as of chassis no. 8E_3_300000), refer to notes for Model Year 2002 v
- Front-wheel drive vehicles as of 01.03 (gradual introduction as of chassis no. 8E_3_300000)
- Front-wheel drive vehicles (2.5 l diesel engine Model Year 2002 only, refer to notes)
- Four-wheel drive vehicles
Checking fuel delivery of metering pump V545 pages
- Unfastening quick-release coupling at auxiliary heater fuel pipe
- Routing of fuel pipe to auxiliary heater
Checking and adjusting CO2 content in exhaust gas of auxiliary heater7 pages
Incorporation of auxiliary heater into coolant circuit6 pages
Removing and installing auxiliary heater7 pages
Dismantling and assembling auxiliary heater47 pages
- Detaching add-on components from heater/re-attaching (version "1”, horizontal installation)
- Detaching add-on components from heater/re-attaching (version "2”, vertical installation)
Detaching/attaching corrugated exhaust pipe3 pages
- Checking auxiliary heater air-intake hose
- Removing and installing auxiliary heater control unit J364
Removing and installing circulation pump V55 (horizontal auxiliary heater installation)3 pages
Removing and installing circulation pump V55 (vertical auxiliary heater installation)2 pages
Dismantling and assembling auxiliary heater (version "1”, horizontal installation)2 pages
- Dismantling and assembling auxiliary heater (version "2”, vertical installation)
Detaching/attaching cover for auxiliary heater sensors3 pages
- Detaching/attaching top part of housing with intake air duct
Removing/installing and checking heater overheating fuse S243 pages
- Affixing auxiliary heater rating plate to housing with heat exchanger
Removing and installing temperature sensor G183 pages
Removing/installing and checking flame monitor G643 pages
Removing and installing burner element with combustion air blower V62 pages
Removing and installing glow plug for heater Q93 pages
- Dismantling and assembling burner element with combustion air blower V6
- Detaching atomiser unit from combustion air blower V6 /attaching
Distinguishing features of atomiser units (for "Petrol” or "Diesel”)3 pages
- Distinguishing features of fuel pressure dampers (for "Petrol” or "Diesel”)
Block diagram of auxiliary heater3 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 conditioning268 pages
Self diagnosis, V.A.G Inspection Service118 pages
Air conditioner self-diagnosis7 pages
Self-diagnosis procedure3 pages
Connecting up vehicle diagnostic, testing and information system VAS 5051A and selecting functions2 pages
Interrogating fault memory4 pages
- Basic setting
Encoding operating and display unit, Climatronic control unit J2553 pages
Reading measured value block37 pages
- List of available measured value blocks (display groups)
Measured value blocks from display group "001” to display group "010”12 pages
- Display group "001”
- Display group "002”
- Explanatory notes on compressor shutoff criterion for display zones "1....4” of display group "002”
- Display group "003”
- Display group "004”
- Display group "005”
- Display group "006”
- Display group "007”
- Display group "008”
- Display group "009”
- Display group "010”
Measured value blocks from display group "011” to display group "020”12 pages
- Display group "011”
- Display group "012”
- Display group "013”
- Display group "014”
- Display group "015”
- Display group "016”
- Display group "017”
- Display group "018”
- Display group "019”
- Table of codes "1” transmitted by dash panel insert (and learnt during "Basic setting” function)
- Table of codes transmitted by control unit in dash panel insert J285 and learnt during "Basic setting” function (codes &q
Measured value blocks as of display group "020”10 pages
- Display groups not used at present for service purposes
Adaption of operating and display unit, Climatronic control unit J2558 pages
- List of adaption channels
- Adaption procedure in the various adaption channels (except adaption channels "08” and "81”)
Adaption procedure for reducing fresh air blower speed (adaption channel 08)2 pages
Chassis number adaption procedure (adaption channel "81”)3 pages
Checking convenience data bus system7 pages
- Function of data bus systems
Checking convenience data bus system5 pages
Electrical checks on air conditioner23 pages
Wiring and component check using test box V.A.G 1598A6 pages
- Special tools, testers and other items required
- Connecting test box V.A.G 1598A to connectors to operating and display unit, Climatronic control unit J255
- Pin assignment of test box V.A.G 1598A with adapter cable V.A.G 1598/11
- Checking
- List of electrical checks at the operating and display unit, Climatronic control unit J255
Test steps "5” to "9”9 pages
- Test step "5”
- Checking pressure signal from high-pressure sender G65
- Pin assignment at high-pressure sender G65
- Pressure signal from high-pressure sender G65
- Test step "6”
- Checking activation signal for air conditioning system compressor regulating valve N280
- Test step "7”
- Test step "8”
Electrical checks on components actuated by operating and display unit, Climatronic control unit J25510 pages
Checking heated seats3 pages
Checking actuation of heated windscreen Z22 pages
Mode of operation of air quality sensor G2384 pages
Checking air quality sensor G2383 pages
Air conditioner150 pages
Safety measures when working on vehicles with air conditioner and for handling refrigerant5 pages
Servicing work on refrigerant circuit4 pages
Detaching compressor from holder/attaching5 pages
Vehicles with 4 or 6-cyl. engine (belt-driven compressor)3 pages
- Vehicles with 8-cyl. engine (shaft-driven compressor)
Replacing pulley/compressor drive unit23 pages
- Replacing pulley (compressor version "1”)
Detaching pulley from compressor/re-attaching (compressor version "1”)3 pages
- Replacing pulley (compressor version "2”)
Detaching pulley from compressor/re-attaching (version "2”)2 pages
- Checking/replacing compressor drive unit
Unfastening and tightening compressor drive shaft3 pages
- Checking concentricity of drive plate with overload safeguard/adjusting
- Removing and installing drive plate with rolling bearing
Components for control and regulation of air conditioner52 pages
- Components in engine compartment and at rear end
- Removing and installing dust and pollen filter
- Dust and pollen filter with activated charcoal filter element
- Checking vent frame
- Components located in passenger compartment
Cleaning evaporator of air conditioner with ultrasonic air conditioner cleaning unit VAS 61893 pages
Removing and installing operating and display unit, Climatronic control unit J2552 pages
- Removing and installing air duct connection for glove box cooling
Removing and installing fresh air blower control unit J126 and fresh air blower V23 pages
- Removing and installing left vent temperature sender G150
- Removing and installing right vent temperature sender G151
- Removing and installing evaporator outflow temperature sender G263
- Removing and installing left footwell vent temperature sender G261
- Removing and installing right footwell vent temperature sender G262
- Removing and installing sunlight penetration photosensor G107
- Checking condensate drain
- Preparing adapter cables for control motor actuation
Removing and installing fresh-air intake duct temperature sensor G893 pages
Dash panel vents and air ducts10 pages
- Air routing in vehicle
- Air routing in air conditioner unit
- Connecting element between temperature flaps "1” and "2”
Removing and installing intermediate piece for windscreen defroster vent3 pages
Removing and installing heating system heat exchanger6 pages
Servicing refrigerant circuit19 pages
Removing and installing compressor11 pages
Removing and installing compressor (vehicles with 4 or 6-cyl. engine)3 pages
Removing and installing compressor (vehicles with 8-cyl. engine)3 pages
- Starting up air conditioner after installing compressor
Removing and installing air conditioner unit4 pages
Dismantling and assembling air conditioner unit4 pages