Components On Left Side Overview
Components on Left Side Overview
• The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, Audi Q5 etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe.
1 Left Seat (Driver's Seat) With Seat Heating and Seat Ventilation Components
• The seat heating and seat ventilation are not installed in all vehicles (optional equipment).
• The A/C Control Head Climatronic control module (J255) adjusts the seat heating and seat ventilation. Activation of seat heater and seat ventilation are displayed in measured value block of Climatronic Control Module, check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Different control units, refer to => [ Front Seat Heating and Ventilation, Checking ] Testing and Inspection , and the Vehicle Diagnostic Tester in "Guided Fault Finding" function, activate the seat heating the seat ventilation, depending on the vehicle equipment and version. (for the Vehicle Electrical System Control Module (J519) , the Memory Seat/Steering Column Adjustment Control Module (J136) and the Passenger Memory Seat Control Module (J521) , depending on the vehicle).
• Repair the seat heating and the seat ventilation.
• For information about seat heating and seat ventilation, refer to => [ Front Seat Heating and Ventilation, Checking ] Testing and Inspection.
• If there is a condition, where the heating or ventilation of the driver of passenger seat cannot be switched on, this will be stored as a malfunction in the Vehicle Electrical System Control Module (J519) , in the Memory Seat/Steering Column Adjustment Control Module (J136) or in Passenger Memory Seat Control Module (J521) (depending on the vehicle type and the vehicle equipment level). Currently no information is sent to the Climatronic control module (J255) display and control head via the data bus system; the DTC memory must be read out in each control unit or in the Comfort System Central Control Module (J393) using the Vehicle Diagnostic Tester in "Guided Fault Finding" function. In the event of a complaint regarding seat heating or seat ventilation, first check the event memory of the control modules activating the seat heating and seat ventilation.
• The seat heating and ventilation is adjusted by the Climatronic control module display and control head; the adjustment is transmitted to the vehicle electrical system control module via the Data bus. The specified temperatures for the different seat heating and seat ventilation settings are stored in the vehicle electrical system control module. Depending on the version of the vehicle electrical system control module and on the vehicle build date, the specified temperature for the seat heating and ventilation can be different with the same setting on the Climatronic control module display and control head. Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function (for the vehicle electrical system control module).
2 Left Condensation Water Drain (Driver Side)
• Checking, removing and installing, refer to => [ Condensation Water Drain Hose ] Condensation Water Drain Hose.
3 Accelerator Pedal
• The request to switch off the A/C compressor kick-down (via the A/C compressor regulator valve (N280) ) comes from the engine control module (the data is exchanged through the Data bus). Read the actual activation of the A/C compressor regulator valve in the Climatronic control module (J255) using the Vehicle Diagnostic Tester under "Guided Fault Finding" (the A/C system and the fuel injection and ignition system).
4 Diagnostic Connection
• Perform Guided Fault Finding for the A/C system using the Vehicle Diagnostic Tester under "Guided Fault Finding".
5 Vehicle Electrical System Control Module (J519)
• The A/C system controls different components, for example, the heated rear window (Z1) via the comfort system central control module (J393). Refer to the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
6 Left Front Upper Body Outlet Temperature Sensor (G385)
- Installed only in the "Comfort" A/C system.
• Removing and installing, refer to => [ Left Front Upper Body Vent Temperature Sensor (G385) ] Left Front Upper Body Vent Temperature Sensor (G385).
7 Defroster Vent/Left Side Window
8 Instrument Panel Vent, Left
• Removing and installing instrument panel vents, refer to => [ Instrument Panel Vents and Rear Vents ] Instrument Panel Vents and Rear Vents.
9 Instrument Cluster Control Module (J285)
• With outside air temperature (G106) in the Driver Information System.
• If there is a complaint due to an excessive display value of outside air temperature (due to an excessive measured value of the Outside Air Temperature Sensor (G17) ), refer to => [ Outside Air Temperature Sensor (G17) ] Outside Air Temperature Sensor (G17).
• Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
10 Front Information Display Control Head (J685)
• Multi Media Interface (MMI) Display
• Different versions and operation; depends on the version of the MMI ("Infotainment" or "Basis") and vehicle equipment. Refer to the Owner's Manual Infotainment / MMI.
• Functions selected (and various additional A/C system functions) on Climatronic Control Module (J255) are indicated via MMI display. Refer to the Owner's Manual Infotainment / MMI.
• Using the "Car" button on the Radio or the Multimedia Control Head (E380) (depending on the vehicle equipment level) additional functions of the A/C system can be called up and their settings can be changed. Refer to the Owner's Manual Infotainment / MMI.
• From MY 2009, on the Audi A5 Coupe and on the Audi A4, a revised Climatronic control module, A/C control head, is being installed (this has been already done on the Audi Q5 since the start of production). Refer to item 14 => [ (Item 14) A/C Control Head of version ] and the Parts Catalog. On vehicles with these A/C control heads, and depending on the coding and adaptation, for example the display on the screen for the "MMI" (Multi Media Interface), when using the buttons and knobs, the A/C control head no longer switches to "A/C system". The selected functions for the A/C system appear in the display sequentially (different versions). Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function, Owner's Manual and Owner's Manual Infotainment / MMI.
• Pay attention to the correct allocation, coding and adaptation for the Climatronic control module, for the Front Information Display Control Head Control Module (J523) / Information Electronics Control Module 1 (J794) (different version depending on the time production and vehicle equipment level), refer to the Parts Catalog. If the allocation, coding and adaptation are incorrect, the A/C function cannot be displayed or selected in the MMI.
• From MY 2012, this vehicle has a Start/Stop System for specific engines as optional equipment. On vehicles with Start/Stop system, the Climatronic control module display and control head prevents the Stop function. If, for example, "defrost" is selected, the stop function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the selected and actual temperature is greater than a specified value. Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Vehicles with the Start/Stop System have an additional coolant pump for the Stop function depending on the vehicle equipment level and on the version of the vehicle. Refer to => [ Coolant Pump ] Coolant Pump.
• If the vehicle has a Start/Stop System, then only the following Climatronic control module may be installed: part number 8T1 820 043 starting with index "AG". Always refer to the Parts Catalog.
11 Air Humidity Sensor (G355)
- Not installed on all vehicles (depends on when the vehicle was manufactured and on the vehicle equipment).
• Checking using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• At the start of production, the humidity sensor was installed only on the "Comfort" A/C system.
• Beginning with the MY 12 Audi A4 and Audi 5, the vehicle version was changed-over as a running change. Refer to => [ Climatronic Control Module (J255) A/C Control Head Allocation ] Climatronic Control Module (J255) A/C Control Head Allocation. Vehicles with the "Basis" A/C system built after the change-over have a humidity sensor.
• The comfort system central control module (J393) or the data bus on board diagnostic interface (J533) evaluates the measured value from the humidity sensor on vehicles manufactured before the change-over. The vehicle electrical system control module (J519) evaluates the measured value from the humidity sensor on vehicles manufactured from the product change-over. Refer to Vehicle Diagnostic Tester in "Guided Fault Finding" function.
12 Radio (R)
• Depending on the vehicle equipment level, instead of a radio, a Multimedia Control Head (E380) may be installed.
• Using the "Car" button, additional A/C system functions can be called up and their settings changed. Refer to the Owner's Manual Infotainment / MMI.
• Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
13 Interior Temperature Sensor Fan (V42) and Instrument Panel Interior Temperature Sensor (G56)
• Installed in the A/C Control Head Climatronic Control Module (J255).
• Interior Temperature Sensor Fan (V42) , removing and installing, refer to => [ Interior Temperature Sensor Fan (V42) ] Service and Repair.
• The Instrument Panel Interior Temperature Sensor (G56) is integrated in the Climatronic control module (cannot be replaced separately).
• On the "Comfort"A/C system, if the intermediate piece on the air guides to the rear footwell vents and on the air guide to the rear center console vents is installed incorrectly, warm or cold air can escape and influence the A/C system. This air is then taken in by the interior temperature sensor fan and the measured value from the instrument panel interior temperature sensor (G56) will differ from the actual temperature inside the passenger compartment.
14 A/C Control Head Climatronic Control Module (J255) of "Basic" version
• Different versions (for vehicles without or with heated seats, left- or right side steering, depending on the time of manufacturer and equipment level), allocation item 15 => [ (Item 15) A/C Control Head of A/C system ] and the Parts Catalog.
• Removing and installing, refer to => [ Climatronic Control Module (J255) A/C Control Head ] Climatronic Control Module (J255) A/C Control Head.
• The Instrument Panel Interior Temperature Sensor (G56) is integrated in the Climatronic Control Module (cannot be replaced separately).
• Interior Temperature Sensor Fan (V42) is installed in Climatronic Control Module, however it cannot be replaced individually. Refer to => [ Interior Temperature Sensor Fan (V42) ] Service and Repair.
• Perform Guided Fault Finding on the Climatronic control module using the Vehicle Diagnostic Tester under "Guided Fault Finding".
• Also pay attention to the information regarding the Climatronic control module. Refer to => [ Climatronic Control Module (J255) A/C Control Head ] Climatronic Control Module (J255) A/C Control Head.
• On the Audi A5 Coupe and Audi A4 from MY 2009, the Climatronic control module, part number 8T1 820 043 starting with the index letter "T" is installed (on the Audi Q5 this was already installed since the start of production). Refer to Electronic Parts Catalog (ETKA) and item 15=> [ (Item 15) A/C Control Head of A/C system ].
• Beginning with MY 2010, the Start/Stop System will be offered as an option for this vehicle with certain engines. Refer to item 15 => [ (Item 15) A/C Control Head of A/C system ] and the Vehicle Diagnostic Tester under "Guided Fault Finding".
• If the vehicle has a Start/Stop System, then only the following Climatronic control module display and control heads may be installed: part number 8T1 820 043 starting with index "AG". Always refer to the Parts Catalog.
• An updated fresh air blower control module (J126) , fresh air blower (V2) , Climatronic control module, vehicle electrical system control module (J519) , comfort system central control module (J393) , air quality sensor (G238) and air conditioner are being installed as a running change from MY 12 (depending on the vehicle version). Pay attention to the version and allocation of these components. 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.
• At the start of production, the humidity sensor (G355) was installed only on the "Comfort" A/C system. The humidity sensor is being installed in vehicles equipped wit the "Basis" A/C system and since the introduction of the Stop/Stop System from MY 10.
• The comfort system central control module (J393) or the data bus on board diagnostic interface (J533) evaluates the measured value from the humidity sensor on vehicles manufactured prior to the version change-over (except Audi Q5 Hybrid). The vehicle electrical system control module evaluates the measured value from the humidity sensor on vehicles manufactured from the product change-over (on all Audi Q5 Hybrid). Refer to and the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Different versions of the humidity sensor in fresh air intake duct / air quality sensor are being installed depending on when the vehicle was manufactured and which A/C system the vehicle has ("Basis" or "Comfort"). The "Basis" A/C system does not have a humidity sensor in fresh air intake duct / air quality sensor until the MY 12 change-over. From MY 12 it has a humidity sensor in fresh air intake duct without an air quality sensor (black housing). Through MY 12, the "Comfort" A/C system has an air quality sensor without a humidity sensor in fresh air intake duct. From MY 12, it has a humidity sensor in fresh air intake duct with an air quality sensor , (brown housing).
• Vehicles with the "Comfort" A/C system have an air quality sensor (G238) without a humidity sensor in fresh air intake duct (G657) (from start of production up the change-over) Refer to the Parts Catalog.
• Beginning with the MY 12 Audi A4 and Audi 5, the vehicle version was changed-over as a running change. Refer to => [ Climatronic Control Module (J255) A/C Control Head Allocation ] Climatronic Control Module (J255) A/C Control Head Allocation. Vehicles, built before the change-over and with the "Comfort" A/C system, have an air quality sensor (G238) (not on the "Basis"). Vehicles built since this change-over (and on the Audi Q5 Hybrid): if the vehicle has the "Basis" A/C system, then it has a humidity sensor in fresh air intake duct (G657) ; if the vehicle has the "Comfort" A/C system, then it has a humidity sensor in fresh air intake duct and an air quality sensor.
• The buttons and rotary switches have LEDs, they cannot be replaced individually.
• The function and indicator lights in the buttons and in the rotary switches cannot be replaced separately.
15 A/C Control Head Climatronic Control Module (J255) of "Comfort" A/C system
• Different versions (for vehicles without or with heated seats / seat ventilation, left- or right side steering, depending on the time of manufacturer and equipment level), allocation, refer to the Parts Catalog.
• Removing and installing, refer to => [ Climatronic Control Module (J255) A/C Control Head ] Climatronic Control Module (J255) A/C Control Head.
• Instrument Panel Temperature Sensor (G56) is integrated in Climatronic Control Module (cannot be replaced individually).
• Interior Temperature Sensor Fan (V42) is installed in Climatronic Control Module, however it cannot be replaced individually. Refer to => [ Interior Temperature Sensor Fan (V42) ] Service and Repair.
• Perform Guided Fault Finding on the Climatronic control module using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• Also pay attention to the information regarding the Climatronic control module. Refer to => [ Climatronic Control Module (J255) A/C Control Head ] Climatronic Control Module (J255) A/C Control Head.
• The buttons, displays and rotatory switches are lit with LEDs; they cannot be replaced individually.
• The function and indicator lights in the buttons and in the rotary switches cannot be replaced separately.
• On the Audi A5 Coupe and Audi A4 from MY 2009, the Climatronic control module, part number 8T1 820 043 starting with the index letter "T" is installed (on the Audi Q5 this was already installed since the start of production). Refer to Electronic Parts Catalog (ETKA). On vehicles with these A/C control heads, and depending on the coding and adaptation, for example the display on the screen for the "MMI" (Multi Media Interface), when using the buttons and knobs, the A/C control head no longer switches to "A/C system". The selected functions for the A/C system appear in the display sequentially. Refer to the Vehicle Diagnostic Tester in "Guided Fault Finding" function, Owner's Manual and Owner's Manual Infotainment / MMI.
• Pay attention to the correct allocation, coding and adaptation of the Climatronic control module, for the Front Information Display Control Head Control Module (J523) / Information Electronics Control Module 1 (J794). Refer to Electronic Parts Catalog (ETKA) and the Vehicle Diagnostic Tester in "Guided Fault Finding" function. If the allocation, coding or adaptation are incorrect, the A/C function cannot be displayed or selected in the MMI.
• The Climatronic control module, part number 8T1 820 043 up to index letter "S" are installed on vehicles with a Front Information Display Control Head Control Module (J523).
• The Climatronic control module, part number 8T1 820 043 beginning with index "T" may be installed on vehicles with an Information Electronics Control Module 1 (J794). In order to be able to select and display the different functions, the coding and adaptation must be correct for the vehicle equipment level.
• Read the information regarding the vehicle updates from MY 12, refer to item 14 => [ (Item 14) A/C Control Head of version ].
16 Multimedia Control Head (E380)
• Depending on the vehicle equipment level, instead of a Multimedia Control Head (E380) a Radio (R) may be installed.
• Using the "Car" button, additional A/C system functions can be called up and their settings changed. Refer to the Owner's Manual Infotainment / MMI.
• Check using the Vehicle Diagnostic Tester in "Guided Fault Finding" function.
• In order to be able to select and display the different A/C system functions on the Multimedia Control Head and on the Front Information Display Control Head (J685) the correct version of the Climatronic control module (J255) , A/C control head, must be installed and coded correctly and adapted. Refer to item 15 => [ (Item 15) A/C Control Head of A/C system ].