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Activation of auxiliary heating > < Operating sequence

A4 Mk3

Requirements for the sequence described on the following pages
Requirements for the sequence described on the following pages
These requirements must be fulfilled on switching on the heater.
l  Coolant circuit bled
l  Battery -A- adequately charged
l  Sufficient fuel in tank.
l  No fault stored in the heater event recorder.
l  Ignition off and “auxiliary heating” mode set
  Note
t  Only the main features of the operating sequence are outlined on the following pages.
t  Certain procedures taking place during auxiliary heater operation are not perceptible (audible or measurable) → Chapter.
t  Depending on vehicle equipment, the circulation pump -V55- may also be actuated when requested by the corresponding engine control unit and the operating and display unit, Climatronic control unit -J255- → Chapter and → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  The heater coolant shut-off valve -N279- may, depending on the coolant temperature and the setting on the operating and display unit, Climatronic control unit -J255-, also be actuated with the auxiliary heater switched off → Chapter and → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  On the Audi Q5, actuation of -N279- is only permissible up to a certain engine speed (currently up to approx. 1200 rpm). Attention is therefore to be paid to the correct version, encoding and adaption of the auxiliary heater → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  The voltages, times and frequencies given in the table are approximate values regulated by the control unit on the basis of measured values (voltage, temperature etc.).
t  1 hertz (Hz) corresponds to 1 pulse per second.
   

Activation of auxiliary heating > < Operating sequence