Manual sections

Wiring diagrams

• 1.8l 4-cyl 5v Turbo Engine Mechanical, Engine Code(s): Amu, Bea
• 1.8l 4-cyl 5v Turbo Engine Mechanical, Engine Code(s): Atc, Awp
• 1.8l 4-cyl 5v Turbo Fuel Injection & Ignition, Engine Code(s): Amu
• 1.8l 4-cyl 5v Turbo Fuel Injection & Ignition, Engine Code(s): Atc
• 1.8l 4-cyl 5v Turbo Generic Scan Tool Engine Code(s): Amu, Bea, Atc, Awp
• 5 & 6-speed Manual Transmission (02m & 02y Awd)
• 5-speed Manual Transmission (02j Fwd)
• 6-speed Automatic Transmission (09g Fwd)
• Abbreviations
• Accessories Control Systems
• Accessory Drive Belts
• Airbag
• Anti-Lock/traction Control
• Automatic HVAC System
• Auxiliary Emission Control Systems
• Axle Shafts
• Basic Trouble Shooting
• Body Collision Repair
• Body Exterior
• Body Interior
• Brake System
• Brakes
• Cabin Air Filter
• Charging System
• Check Lists
• Clutches - 02j (fwd)
• Clutches - 02m (5 & 6-speed Awd)
• Computer Relearn
• Cooling Fan
• Cooling System (mechanical)
• Diagnostic Connector Locations
• Differentials & Drive Axles
• Door Locks & Anti-Theft Systems
• Drive Cycles
• Driveline/axles
• DTC Index
• Electrical Component Locations
• Electrical Equipment
• Electrical Equipment - General Information
• Emission Applications
• Engine
• Engine Performance
• Exhaust
• Exterior Body Panels
• Fuel Supply System
• Fuses & Circuit Breakers
• Gauges & Instrument Panels
• General Servicing - All Makes
• Heating & Air Conditioning
• Identification
• Ignition System
• Manual Trans
• MAP Guidelines
• Mechanical - Hydraulic
• Metric Conversions
• Oem General Information
• Procedures
• Rear Final Drive 02d
• Reset Procedures
• Restraints
• Specifications
• Starter
• Steering
• Steering Column Switches
• Suspension Front
• Suspension Rear
• Suspension, Wheels, Steering
• Timing Belt
• Traction Control Disable
• Transmission
• Wheel & Tire System
• Wheel Alignment
• Windows

Repair manual

Heating & Air Conditioning Audi TT 8N

Step-by-step instructions on "Heating & Air Conditioning" for Audi TT 8N (1998–2003). Pick an article — removal, installation, adjustment and diagnostics with illustrations.

127subsections

127articles

98illustrations

Automatic Climate Control system, On Board Diagnostic (OBD)

1 article

• Automatic Climate Control system, On Board Diagnostic (OBD)

Function

1 article

• Function

On Board Diagnostic (OBD) technical data

1 article

• On Board Diagnostic (OBD) technical data

On Board Diagnostic (OBD), test requirements

1 article

• On Board Diagnostic (OBD), test requirements

Scan Tool (ST) and test equipment safety precautions

1 article

• Scan Tool (ST) and test equipment safety precautions

Scan Tool (ST) and test equipment safety precautions, continued

1 article

• Scan Tool (ST) and test equipment safety precautions, continued

VAG 1551 Scan Tool (ST), VAS 5051 Vehicle Diagnostic Testing and Information System, connecting and selecting functions

1 article

• VAG 1551 Scan Tool (ST), VAS 5051 Vehicle Diagnostic Testing and Information System, connecting and selecting functions 1

Coding table

1 article

• Coding table

Diagnostic Trouble Code (DTC) Memory, checking (function 02)

1 article

• Diagnostic Trouble Code (DTC) Memory, checking (function 02)

Diagnostic Trouble Code (DTC) table

1 article

• Diagnostic Trouble Code (DTC) table

Output Diagnostic Test Mode (DTM) (function 03)

1 article

• Output Diagnostic Test Mode (DTM) (function 03)

Idle Air Control (IAC) regulation, initiating Output Diagnostic Test Mode (DTM)

1 article

• Idle Air Control (IAC) regulation, initiating Output Diagnostic Test Mode (DTM)

Basic Setting (function 04)

1 article

• Basic Setting (function 04)

Diagnostic Trouble Code (DTC) Memory, erasing and End Output (functions 05 and 06)

1 article

• Diagnostic Trouble Code (DTC) Memory, erasing and End Output (functions 05 and 06)

Control Module, coding (function 07)

1 article

• Control Module, coding (function 07)

Read Measuring Value Block (function 08)

1 article

• Read Measuring Value Block (function 08)

Overview of display group numbers which can be selected

1 article

• Overview of display group numbers which can be selected

Display group 001 - Compressor cut-off conditions, voltage for A/C clutch and at terminal 15

1 article

• Display group 001 - Compressor cut-off conditions, voltage for A/C clutch and at terminal 15

Display group 002 - Temperature regulator flap motor -V68

1 article

• Display group 002 - Temperature regulator flap motor -V68

Display group 003 - Central air flap motor -V70

1 article

• Display group 003 - Central air flap motor -V70

Display group 004 - Footwell/defroster flap motor -V85

1 article

• Display group 004 - Footwell/defroster flap motor -V85

Display group 005 - Air flow flap motor -V71

1 article

• Display group 005 - Air flow flap motor -V71

Display group 006 - Calculated ambient temperature for outside air temperature display -G106-, measured values from fresh air intake duct temperature sensor -G89- and outside air t

1 article

• Display group 006 - Calculated ambient temperature for outside air temperature display -G106-, measured values from fresh air intake duct temperature sensor -G89- and outside air t

Display group 007 - Sender for outlet temperature, floor outlet -G192-, instrument panel interior temperature sensor -G56-, calculated coolant temperature

1 article

• Display group 007 - Sender for outlet temperature, floor outlet -G192-, instrument panel interior temperature sensor -G56-, calculated coolant temperature

Display group 008 - Voltage at fresh air blower -V2- and voltage at terminals 58d/s

1 article

• Display group 008 - Voltage at fresh air blower -V2- and voltage at terminals 58d/s

Display group 009 - Engine speed (RPM), vehicle speed, auxiliary heater and key allocation

1 article

• Display group 009 - Engine speed (RPM), vehicle speed, auxiliary heater and key allocation

Display group 010, display fields 1 - 3 - Excessive coolant temperature signal, A/C compressor cut-in/out, A/C pressure switches -F129-/-G65, signal from convertible top control mo

1 article

• Display group 010, display fields 1 - 3 - Excessive coolant temperature signal, A/C compressor cut-in/out, A/C pressure switches -F129-/-G65, signal from convertible top control mo

Display group 010, display field 4 - Signal from convertible top control module -J256

1 article

• Display group 010, display field 4 - Signal from convertible top control module -J256

Display group 011 (last four compressor cut-off conditions recognized)

1 article

• Display group 011 (last four compressor cut-off conditions recognized)

A/C Control Head -E87-, electrical testing

1 article

• A/C Control Head -E87-, electrical testing 1

Socket assignment for VAG 1598 test box with adapter lead VAG 1598/11

1 article

• Socket assignment for VAG 1598 test box with adapter lead VAG 1598/11

Test step 1 - Voltage supply, Ground (GND) connection, illumination for A/C Control Head -E87-, signal for "ignition off" period

1 article

• Test step 1 - Voltage supply, Ground (GND) connection, illumination for A/C Control Head -E87-, signal for "ignition off" period

Test step 2 - Temperature sensors/sensors (-G17-, G98-, G192-)

1 article

• Test step 2 - Temperature sensors/sensors (-G17-, G98-, G192-)

Resistance values (dependent on ambient temperature) for temperature sensors in k ohms

1 article

• Resistance values (dependent on ambient temperature) for temperature sensors in k ohms

Test step 3 - Fresh air blower -V2- with control module -J126

1 article

• Test step 3 - Fresh air blower -V2- with control module -J126

Test step 4 - A/C flap position sensors (in flap motors) (-V68-/-G92-, -V70-/G112-, -V71-/-G113-, -V85-/-G114-)

1 article

• Test step 4 - A/C flap position sensors (in flap motors) (-V68-/-G92-, -V70-/G112-, -V71-/-G113-, -V85-/-G114-)

Test step 5 - A/C pressure switch -F129-, signal from Coolant Fan Control (FC) Module -J293-, output for "A/C compressor cut-in/out", signal indicating "excessive coolant temperatu

1 article

• Test step 5 - A/C pressure switch -F129-, signal from Coolant Fan Control (FC) Module -J293-, output for "A/C compressor cut-in/out", signal indicating "excessive coolant temperatu

Test step 6 - Activation of coolant fan(s) -V7-, activation of A/C clutch -N25

1 article

• Test step 6 - Activation of coolant fan(s) -V7-, activation of A/C clutch -N25

Coolant Fan Control (FC) Module -J293-, electrical testing

1 article

• Coolant Fan Control (FC) Module -J293-, electrical testing 4

Test step 1 - Voltage supply, Ground (GND) supply

1 article

• Test step 1 - Voltage supply, Ground (GND) supply

Test step 2 - Activation of coolant fan(s) -V7

1 article

• Test step 2 - Activation of coolant fan(s) -V7

Test step 3 - Activation of A/C clutch -N25

1 article

• Test step 3 - Activation of A/C clutch -N25

Test step 4 - Signal from high pressure sensor -G65

1 article

• Test step 4 - Signal from high pressure sensor -G65 4

A/C refrigerant system, safety measures

1 article

• A/C refrigerant system, safety measures

A/C refrigerant system, general repair guidelines

1 article

• A/C refrigerant system, general repair guidelines 1

Commercial designation

1 article

• Commercial designation

Color

1 article

• Color

Airborne properties

1 article

• Airborne properties

Solubility of refrigerant oil

1 article

• Solubility of refrigerant oil

Effects on the environment

1 article

• Effects on the environment

Toxicity

1 article

• Toxicity

Temperature/pressure relationship

1 article

• Temperature/pressure relationship

Effects on plastics

1 article

• Effects on plastics

Effects on metal

1 article

• Effects on metal

Critical temperature/critical pressure

1 article

• Critical temperature/critical pressure

Water solubility

1 article

• Water solubility

Flammability

1 article

• Flammability

Refrigerant containers

1 article

• Refrigerant containers

Leak detection

1 article

• Leak detection

A/C refrigerant oil (PAG), properties

1 article

• A/C refrigerant oil (PAG), properties

A/C refrigerant system, servicing

1 article

• A/C refrigerant system, servicing 1

A/C pressure switch -F129-, switch functions

1 article

• A/C pressure switch -F129-, switch functions 1

Checking

1 article

• Checking 1

A/C refrigerant system, quick coupling service connections

1 article

• A/C refrigerant system, quick coupling service connections 3

Pressure and temperature specifications

1 article

• Pressure and temperature specifications

A/C Clutch -N25-, servicing

1 article

• A/C Clutch -N25-, servicing 13

A/C system control and regulation components in engine compartment and rear body

1 article

• A/C system control and regulation components in engine compartment and rear body 1

Evaporator housing drain valve, checking, removing and installing

1 article

• Evaporator housing drain valve, checking, removing and installing 1

Receiver drier, removing and installing

1 article

• Receiver drier, removing and installing 1

Condenser, removing and installing

1 article

• Condenser, removing and installing 2

Refrigerant pipes on expansion valve, removing and installing

1 article

• Refrigerant pipes on expansion valve, removing and installing 1

Expansion valve, removing and installing

1 article

• Expansion valve, removing and installing 2

Refrigerant pipes on compressor, removing and installing

1 article

• Refrigerant pipes on compressor, removing and installing 1

A/C Compressor - 4-cyl. engine, removing from bracket (refrigerant pipes remain connected)

1 article

• A/C Compressor - 4-cyl. engine, removing from bracket (refrigerant pipes remain connected) 2

A/C compressor, removing and installing

1 article

• A/C compressor, removing and installing

A/C system control and regulation components in passenger compartment

1 article

• A/C system control and regulation components in passenger compartment 1

A/C Control Head -E87-, removing and installing

1 article

• A/C Control Head -E87-, removing and installing 2

Interior temperature sensor fan -V42-, removing and installing

1 article

• Interior temperature sensor fan -V42-, removing and installing 1

Control module for fresh air blower -J126-, removing and installing

1 article

• Control module for fresh air blower -J126-, removing and installing 1

Sender for outlet temperature, floor outlet -G192-, removing and installing

1 article

• Sender for outlet temperature, floor outlet -G192-, removing and installing 1

Fresh air blower -V2-, removing and installing

1 article

• Fresh air blower -V2-, removing and installing 4

Sunlight photo sensor -G107-, removing and installing

1 article

• Sunlight photo sensor -G107-, removing and installing 5

Footwell/defroster flap motor -V85-, removing and installing

1 article

• Footwell/defroster flap motor -V85-, removing and installing 1

Temperature regulator flap motor -V68-, removing and installing

1 article

• Temperature regulator flap motor -V68-, removing and installing 1

Central air flap motor -V70-, removing and installing

1 article

• Central air flap motor -V70-, removing and installing 1

Fresh air intake duct temperature sensor -G89-, removing and installing

1 article

• Fresh air intake duct temperature sensor -G89-, removing and installing 1

Air flow flap motor -V71-, removing and installing

1 article

• Air flow flap motor -V71-, removing and installing 3

Heating and A/C unit (with heater core and evaporator), removing and installing

1 article

• Heating and A/C unit (with heater core and evaporator), removing and installing 2

Heater core/coolant flow direction configurations

1 article

• Heater core/coolant flow direction configurations 20

Refrigerant pipe seal at evaporator, installing

1 article

• Refrigerant pipe seal at evaporator, installing 1

Air distribution system (air vents and ducts), servicing

1 article

• Air distribution system (air vents and ducts), servicing 3

Undamaged instrument panel vents, removing and installing

1 article

• Undamaged instrument panel vents, removing and installing 1

Windshield defroster vent, removing and installing

1 article

• Windshield defroster vent, removing and installing

Defroster vent air duct, removing and installing

1 article

• Defroster vent air duct, removing and installing 3

Footwell duct/vent, removing and installing

1 article

• Footwell duct/vent, removing and installing

Heater core, removing and installing

1 article

• Heater core, removing and installing

Heating and A/C unit (with heater core and evaporator) mechanical components, overview

1 article

• Heating and A/C unit (with heater core and evaporator) mechanical components, overview

Tensioning strap, installing

1 article

• Tensioning strap, installing

Installing wiring harness for air conditioner

1 article

• Installing wiring harness for air conditioner

Evaporator housing seal, location

1 article

• Evaporator housing seal, location

Heating and A/C unit (with heater core and evaporator) electrical components, overview

1 article

• Heating and A/C unit (with heater core and evaporator) electrical components, overview

Heating and A/C unit (with heater core and evaporator), disassembly and assembly

1 article

• Heating and A/C unit (with heater core and evaporator), disassembly and assembly

Air distribution housing, assembly

1 article

• Air distribution housing, assembly

Evaporator seal, installing

1 article

• Evaporator seal, installing

A/C cooling performance, testing

1 article

• A/C cooling performance, testing 1

Identifying malfunctions if specified values are not obtained

1 article

• Identifying malfunctions if specified values are not obtained

Damaged instrument panel vents, removing and installing

1 article

• Damaged instrument panel vents, removing and installing

Dust and pollen filter, removing and installing

1 article

• Dust and pollen filter, removing and installing 1

Air extraction vents, checking

1 article

• Air extraction vents, checking

A/C refrigerant system, leak testing

1 article

• A/C refrigerant system, leak testing 1

A/C refrigerant system, testing with pressure gauges

1 article

• A/C refrigerant system, testing with pressure gauges

A/C refrigerant system pressures, checking

1 article

• A/C refrigerant system pressures, checking

If A/C refrigerant system pressure is less than specified on chart, system is low on refrigerant

1 article

• If A/C refrigerant system pressure is less than specified on chart, system is low on refrigerant

If A/C refrigerant system pressure corresponds to or is higher than pressure specified on chart (vehicles with expansion valve and receiver drier)

1 article

• If A/C refrigerant system pressure corresponds to or is higher than pressure specified on chart (vehicles with expansion valve and receiver drier) 1

Troubleshooting tables

1 article

• Troubleshooting tables

A/C refrigerant system, replacing components

1 article

• A/C refrigerant system, replacing components

For leaking or damaged components (except for compressor and receiver drier), A/C system was completely empty (no charge)

1 article

• For leaking or damaged components (except for compressor and receiver drier), A/C system was completely empty (no charge)

For leaky or damaged components (except for the compressor and receiver drier) there is still refrigerant oil in the system component that must be accounted for when replacing

1 article

• For leaky or damaged components (except for the compressor and receiver drier) there is still refrigerant oil in the system component that must be accounted for when replacing

Replace compressor, without it being necessary to blow through the refrigerant system with compressed air and nitrogen (e.g. exterior damage after an accident)

1 article

• Replace compressor, without it being necessary to blow through the refrigerant system with compressed air and nitrogen (e.g. exterior damage after an accident)

Replace compressor due to leaks or internal damage (e.g. noises or no power)

1 article

• Replace compressor due to leaks or internal damage (e.g. noises or no power)

Replace receiver drier after blowing through the A/C system e.g. caused by moisture contamination (the A/C system was open over a long period of time) or contamination (dirt)

1 article

• Replace receiver drier after blowing through the A/C system e.g. caused by moisture contamination (the A/C system was open over a long period of time) or contamination (dirt)

Replace receiver drier, without it being necessary to blow through A/C system with compressed air and nitrogen (e.g. damage caused by an accident), no refrigerant flowed out and no

1 article

• Replace receiver drier, without it being necessary to blow through A/C system with compressed air and nitrogen (e.g. damage caused by an accident), no refrigerant flowed out and no

A/C refrigerant system, symptom based troubleshooting

1 article

• A/C refrigerant system, symptom based troubleshooting

A/C refrigerant system, discharging

1 article

• A/C refrigerant system, discharging 1

A/C refrigerant system, evacuating and recharging

1 article

• A/C refrigerant system, evacuating and recharging

A/C refrigerant R-134a and refrigerant oil (PAG), capacities

1 article

• A/C refrigerant R-134a and refrigerant oil (PAG), capacities

A/C refrigerant system (R-134a), flushing with compressed air and nitrogen

1 article

• A/C refrigerant system (R-134a), flushing with compressed air and nitrogen