Climatronic Control Module (J255) A/C Control Head Allocation
Climatronic Control Module (J255) A/C Control Head Allocation
• Beginning 08.2007 the "Comfort" A/C system with an air distribution housing with optimized air distribution will be introduced (distinguishing characteristic between versions "1" and "2". Refer to => [ Comfort A/C Unit and Air Distribution Housing ] Comfort A/C Unit and Air Distribution Housing and the Parts Catalog).
• The coolant pump (V50) ( water pump (V36) ) control differs and depends on the date of manufacture.
• The coolant pump (water pump) versions and activation differ depending on the version of the vehicle and production period. From MY 12 beginning with start of production, pumps that were controlled by a 500 Hertz signal (500 pulses per second) are being replaced by pumps that are controlled by a 100 Hertz signal depending on the engine. Pumps, controlled by a 100 Hertz signal, also have a diagnostic function and are controlled by the engine control module. Check for the correct allocation. Refer to the Vehicle diagnostic tester in "Guided Fault Finding", and the Parts Catalog.
- On vehicles with a version "2" A/C system, the Climatronic control module for the "Comfort" A/C system with part number "8T1 820 043" beginning with the index letter "Q" is or will be installed.
- If on vehicles with the version "1" A/C system, a Climatronic control module with the "Comfort" A/C system, with part number "8T1 820 043" beginning with the letter "Q" is installed. The adaptation is changed in adaptation channel 18 using the Vehicle diagnostic tester in "Guided Fault Finding".
• There is a label - A - on the outside of the A/C unit with a part - B - that tells which version is installed. Refer to the Parts Catalog.
• The part number - B - on the decal - A - can be read when the CD changer is removed (depending on the vehicle equipment level). Refer to Electronic Parts Catalog (ETKA).
- The Climatronic control module for the "Comfort" A/C system with part number "8T1 820 043" through letter "S" may not be installed in the version "2" A/C.
• On the "Basis" A/C system, the A/C unit and the air distribution housing were not changed.
• 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. Check with the the Vehicle diagnostic tester in "Guided Fault Finding", the Owner's Manual and the 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". 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) and 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.
• From MY 2010, this vehicle has a Start/Stop System for specific engines as optional equipment.
• As a running change in MY 10, gasoline engines that can run on bioethanol (Flex Fuel Vehicles) were introduced
• On vehicles with Start/Stop system, the Climatronic control module 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 shown using the Vehicle diagnostic tester in "Guided Fault Finding".
• Only Climatronic control modules with part number 8T1 820 043 from index "AG" or with part number 8K_ 820 043 are or will be installed in vehicles equipped with the Start/Stop System. Refer to the Parts Catalog and the Vehicle diagnostic tester in "Guided Fault Finding".
• The coolant pump (V50) ( water pump (V36) ) differs and depends on the date of manufacture and on the version of the vehicle. Make sure to use the correct version of the Climatronic control module. Note that a Climatronic control module, part number 8T1 820 043 starting with index "AG" must also adapt the cooling pump (water pump) control. Refer to => [ Coolant Recirculation Pump (V50) (Water Pump (V36)) ] Coolant Recirculation Pump (V50) (Water Pump (V36)) and to the Vehicle diagnostic tester in "Guided Fault Finding".
• The coolant pump (water pump) versions and activation differ depending on the version of the vehicle and production period. From MY 12 beginning with start of production, pumps that were controlled by a 500 Hertz signal (500 pulses per second) are being replaced by pumps that are controlled by a 100 Hertz signal depending on the engine. Pumps, controlled by a 100 Hertz signal, also have a diagnostic function and are controlled by the engine control module. Check for the correct allocation. Refer to the Vehicle diagnostic tester in "Guided Fault Finding", and to the Parts Catalog.
• As a running change in MY 10, gasoline engines that can run on bioethanol (Flex Fuel Vehicles) were introduced, which currently have an auxiliary heater heating element (Z35). Refer to => [ Auxiliary Heater Heating Element (Z35), Testing ] Testing and Inspection. The activation of the auxiliary heater heating element) occurs for vehicles with a gasoline engine from the Climatronic control module via the local Data bus (controlled using the same outlet and also using the fresh air blower control module (J126) ) on the auxiliary air heater control module (J604).
• Only Climatronic control modules with part number 8T1 820 043 from index "AG" or with part number 8K_ 820 043 are or will be installed in vehicles equipped with a gasoline engine that can also run on bioethanol. Refer to the Parts Catalog and the Vehicle diagnostic tester in "Guided Fault Finding".
• Vehicles with a high voltage system ( hybrid vehicles)
• Only the Climatronic control module, part number 8R1 820 043, may be installed on vehicles with a high voltage system (only for LHD vehicles until the version change-over) (from MY 12 see below). Refer to the Parts Catalog and the Vehicle diagnostic tester in "Guided Fault Finding".
• Climatronic control module, part number 8R1 820 043, may be installed only in high voltage vehicles through the vehicle version change-over (from MY 12 see below). After the model year change-over, Climatronic control module, part number 8K_ 820 043, is being installed in high voltage vehicles. Pay attention to the part number index and coding. Refer to the Parts Catalog and the Vehicle diagnostic tester in "Guided Fault Finding".
• Vehicles built after the version change-over can only use one the different Climatronic control modules listed. A Climatronic control module, with part number 8K_ 820 043 and index "K or AA" through index "P or AE" does not have the necessary functions needed by high voltage vehicles. These functions are integrated in a Climatronic control module with part number 8K_ 820 043 from index "Q or AF". Instead of a Climatronic control module with part number 8Kx 820 043 and index "Q", a control module with index "AF" can be installed (the function for controlling the A/C clutch (N25) is not used). Refer to the Parts Catalog=>. The coding in the Climatronic control module turns off or activates the necessary functions for the vehicle. Refer to the Vehicle diagnostic tester in "Guided Fault Finding function".
• From MY 12, as a running change (depending on the model and version), a revised Climatronic control module is being installed. Refer to the Parts Catalog.
• From MY 12, the change-over was made on the Audi A4 and Audi A5 as a running change. Vehicles built before the change-over may only have Climatronic control module with part number 8T__ 820 043 may be installed (only Climatronic control module with part number 8R1 820 043 may be installed on high voltage vehicles). Vehicles manufactured after the change-over may only have Climatronic control module with part number 8K_ 820 043. Refer to the Parts Catalog and the Vehicle diagnostic tester in "Guided Fault Finding".
• When the "Comfort" A/C system is installed, the Climatronic control module with part number 8T_ 820 043 (with part number 8R1 820 043) - A -) and with part number 8K_ 820 043 - B - and be differentiated as follows: the Climatronic control module - A - installed from start of production (part number 8T_ 820 043 / 8R1 820 043) the seat heating and ventilation are controlled by the buttons - C - and the rotary switch. From the vehicle version change-over (from MY 12 as a running change) on the installed Climatronic control module - B - (part number 8K_ 820 043 ) two separate buttons - D - and - E - operate the seat heating and seat ventilation. The location of the buttons - F - and - G - is different between both versions.
• The seat heating and seat ventilation can be adjusted separately in 3 speed with the introduction of the Climatronic control module , version - B -. Refer to the Owner's Manual.
• When installed on the "Basis" A/C system, the Climatronic control module with part number 8T_ 820 043 (with part number 8R1 820 043) - A -) and with part number 8K_ 820 043 - B - can be differentiated as follows: Both versions - A - and - B - can be differentiated by the rotary adjuster (version - B - with a chrome ring) and by the seat heating buttons. The seat symbols in the buttons - C - and - D - point in different directions on the Climatronic control module - A - installed from start of production. When the Climatronic control module - B - is installed, the seat symbols on the buttons - C - and - D - point in the same direction from the vehicle version change-over (from MY 12 as a running change).
• The seat heating can be adjusted separately in 3 speeds with the introduction of the Climatronic control module , version - B -. Refer to the Owner's Manual.
• 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 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 the Vehicle diagnostic tester in "Guided Fault Finding" function.
• There is a label - A - on the outside of the A/C unit with a part - B - that tells which version is installed. Refer to the Parts Catalog.
• The part number - B - on the decal - A - can be read when the CD changer is removed (depending on the vehicle equipment level). Refer to Electronic Parts Catalog (ETKA).
• There are different versions of the coolant recirculation pump (V50) ( water pump (V36) ) installed depending on the vehicle version and on the engine and when the vehicle was manufactured as a running change from MY 12. How the pumps are controlled is also different. From the start of MY 12, pumps, which were controlled by a 500 Hertz signal (500 pulses per second), are replaced by 100 Hertz signal pumps. Pumps, controlled by a 100 Hertz signal, also have a diagnostic function and are controlled by the engine control module. Check for the correct allocation, refer to the Vehicle diagnostic tester in "Guided Fault Finding", and to the Parts Catalog.
• An A/C compressor with an A/C clutch (N25) is installed as a running change on certain 4 cylinder vehicles from MY 12.
• The A/C clutch turns off the A/C compressor drive completely under certain conditions (for example "ECON"). The correct Climatronic control module must be installed and it must be coded correctly so that the Climatronic control module can control the A/C clutch. Refer to the Parts Catalog and to the Vehicle diagnostic tester in "Guided Fault Finding".
• In order for the Climatronic control module to be able to control the A/C clutch, only one Climatronic control module must be installed in these vehicles that has the necessary functions to control the A/C clutch (Climatronic control module with part number 8K_ 820 043 and index "K" cannot control an A/C clutch). Climatronic control module with part number 8K_ 820 043 and index "AA" can control the A/C clutch. In place of a Climatronic control module with part number 8K_ 820 043 and index "K", a version with index "AA" (controlling the A/C clutch is not used) or index "AF" (controlling the A/C or high voltage vehicles is not used) can be installed. Refer to the Parts Catalog. The coding in the Climatronic control module turns off or activates the necessary functions for the vehicle. Refer to the Vehicle diagnostic tester in "Guided Fault Finding" function.