CLIMATRONIC Control Module A/C Control Head Comfort Version

The display unit of the Climatronic Control Module -J255- control head temperature display in degrees Celsius or degrees Fahrenheit is transferred by the MMI (Multi Media Interface) via the Comfort data bus system and determined by the setting entered there.
The Climatronic Control Module -J255- A/C control head Comfort version -A- is available in the following variants (with or without buttons for heated seats, for vehicles with left or right-hand steering, with a button -C- with the ECON ON/OFF function, or just an ON/OFF button).

Fig 1: Identifying A/C System Components
Courtesy of AUDI OF AMERICA, LLC
On the Climatronic Control Module -J255- A/C control head Comfort version -A-, both control knobs -D- can be pulled off and thereby be replaced individually.
For a faulty measurement by instrument panel interior temperature sensor -G56- (installed only on the Climatronic Control Module -J255- A/C control head Comfort version -A-), check intake grille -B- of trim panel for the Climatronic Control Module -J255- A/C control head, (it must not be closed) and function of interior temperature sensor fan -V42- using the Vehicle Diagnostic, Testing and Information SystemVAS 5051.
The Climatronic Control Module -J255- A/C control head Comfort version can be set into operation for a certain period of time (up to approximately 30 minutes) after switching off ignition by pressing the ECON ON/OFF or ON/OFF button (the operating time depends on the battery charge state, it is approximately 10 minutes). Refer to Owner's Manual and using the Vehicle Diagnostic, Testing and Information SystemVAS 5051.
The humidity sensor is installed near the temperature sensor -G56- in the Climatronic Control Module -J255- A/C control head (cannot be replaced individually).
Starting with model year 2009, the Climatronic Control Module -J255- A/C control head Comfort version is gradually being installed, with part no. 4F1 820 043 as of index AK (vehicles with left-hand steering), or part no. 4F2 820 043 as of index T (vehicles with right-hand steering. On vehicles with these A/C control heads, for example the screen in the MMI (Multi Media Interface) display will not switch to A/C system when the buttons and knobs on the A/C control head are pressed. The selected A/C system functions are shown in the running display. Refer to Owner's Manual and Infotainment/MMI Owner's Manual. For this A/C control head, the Setup button is replaced with the A/C button and the ECON ON/OFF button is replaced with the ON/OFF button. Refer to Owner's Manual.

NOTE:

On vehicles that have a Climatronic Control Module -J255- A/C control head Comfort version without the Setup button, select and activate the additional A/C system functions through the rotary push-button of the MMI control unit. Refer to Owner's Manual and Infotainment/MMI Owner's Manual.

Pay attention to the correct allocation of the Climatronic Control Module -J255- A/C control head, Comfort version, to the front information -J523- control head/to the control module for information electronics 1 -J794- (the -J255- control head in the Comfort with the Setup button are installed in vehicles with an front information -J523- control head, and the -J255- control head Comfort version without the Setup button are installed in vehicles with a control module for information electronics 1 -J794-) If the allocation is incorrect, various A/C system functions cannot be displayed and selected or selected in the MMI.