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Climatronic Control Module A/C Control Head Comfort Version






Climatronic Control Module A/C Control Head Comfort Version

The display unit of the Climatronic Control Module (J255) control head temperature display in °C or °F 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).





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) => Vehicle Diagnosis, Testing and Information System VAS 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). => Owner's Manual and => Vehicle Diagnosis, Testing and Information System VAS 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, e.g. 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 => 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 => Owner's Manual.

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 => 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.