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Checking of electrical components actuated by the air conditioner > < Contact corrosion

A4 Mk3

Checking of electrical air conditioner components actuated or evaluated by way of other control units
Checking of electrical air conditioner components actuated or evaluated by way of other control units
  Note
t  Various air conditioner components are no longer actuated directly by the air conditioner operating and display unit, Climatronic control unit -J255-. The air conditioner compressor regulating valve -N280- for example is actuated by way of the onboard supply control unit -J519-. The data are exchanged between the two control units by way of the data bus → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
t  The measured values of various air conditioner components are no longer evaluated directly by the air conditioner operating and display unit, Climatronic control unit -J255-. Thus, for example, the pressure signal from the refrigerant pressure and temperature sender -G395- is evaluated by the onboard supply control unit -J519- and the measured values are transmitted via the data bus to the air conditioner operating and display unit, Climatronic control unit -J255- → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051 and → Current flow diagrams, Electrical fault finding and Fitting locations.
t  As of Model Year 2010 a start/stop system will be available as an optional extra for this vehicle in conjunction with certain engines. The stop function may be inhibited by the operating and display unit, Climatronic control unit -J255- depending on its setting. If „Defrost“ mode has been set for example, no stop function is possible or the stop function is terminated and the engine started as soon as this mode is selected. This also applies if the difference between the set specified temperature and the measured actual temperature exceeds a certain value in heating and cooling mode → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
   

Checking of electrical components actuated by the air conditioner > < Contact corrosion