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Technical data of self-diagnosis > < Connecting vehicle diagnostic tester

A4 Mk2

  • Heating, ventilation, air conditioning system
  • Auxiliary heater
  • Self diagnosis, V.A.G Inspection Service
  • Auxiliary heater self-diagnosis

Auxiliary heater self-diagnosis
Auxiliary heater self-diagnosis
  Note
t  Auxiliary heater control remains operative during self-diagnosis.
t  On this vehicle, the diagnostic connections of various control units (e.g. auxiliary heater, radio) are wired to a different diagnostic connector pin. To permit the exchange of data with these control units, the diagnostic wire between the vehicle and the vehicle diagnostic system (e.g. vehicle diagnostic, testing and information system -VAS 5051A- or vehicle diagnostic and service information system -VAS 5052-) must be fitted with the K-wire adapter -VAS 6017B- (or the K-wire adapter -VAS 6017A-) → Current flow diagrams, Electrical fault finding and Fitting locations.
t  As of chassis number “400000” in Model Year 2005 (Saloon and Avant; gradual introduction for the Cabrio in week 46/04 with no prior specification of any particular chassis number → Parts List) and depending on vehicle equipment, certain control units will no longer be connected to the K / L-wire of the 16-pin diagnostic socket in the vehicle (e.g. engine control unit -J623-, automatic gearbox control unit -J217- and airbag control unit -J234-) → Current flow diagrams, Electrical fault finding and Fitting locations. These control units use “CAN signal wires” to exchange information for example with the vehicle diagnostic, testing and information system -VAS 5051A-. As the K-wire adapter -VAS 6017A- is not provided with these connections, the K-wire adapter -VAS 6017B- is required for the self-diagnosis of these control units.
t  In order to be able to perform self-diagnosis with the fault reader -V.A.G 1551- or the vehicle system tester -V.A.G 1552- on this vehicle, the program card in the fault reader -V.A.G 1551- must correspond to at least data level “No. 9” and in the vehicle system tester -V.A.G 1552- to at least data level “No. 6”. For vehicles as of chassis number “400000” in Model Year 2005 (Saloon and Avant; gradual introduction for the Cabrio in week 46/04 with no prior specification of any particular chassis number → Parts List), self-diagnosis using the fault reader -V.A.G 1551- or the vehicle system tester -V.A.G 1552- will no longer be possible for all vehicle systems.
t  There are different auxiliary heater versions.
t  Pay attention to the exact assignment when replacing an auxiliary heater → Parts List.
   
t  The version is indicated on the rating plate -A- of the heaters:
t  Type “912- D” = Auxiliary heater (with supplementary heater; for vehicles with diesel engine only)
t  Type “912- B” = Auxiliary heater (for vehicles with petrol engine only)
  A82-0401
t  A second rating plate (duplicate) -A- is provided in the engine compartment. In cases of doubt concerning the type of auxiliary heater, always refer to the rating plate affixed to the actual auxiliary heater.
t  Information on the year of initial commissioning of the auxiliary heater can be found in section -B-.
t  If the assignment of the auxiliary heater control unit -J364- (rating plate) differs from the fault reader display, check the adaption (adaption channel “05”). If the type of fuel has been altered in this channel, the setting in the auxiliary heater control unit -J364- changes the first time the ignition is switched on (the type of fuel transmitted by way of the convenience data bus system must coincide with that entered in the “Adaption” function).
On vehicles with diesel engine not fitted with an electric supplementary heating system, heaters of type “912- D” are also used as supplementary heaters → Audi Sales Range → Air conditioning; Rep. Gr.01 and → Heating; Rep. Gr.01.
The supplementary heater is switched on by the operating and display unit, Climatronic control unit -J255- by way of the convenience data bus system as soon as the activation conditions specified in the operating and display unit, Climatronic control unit -J255- have been fulfilled → Current flow diagrams, Electrical fault finding and Fitting locations, → Air conditioning; Rep. Gr.01 and → Heating; Rep. Gr.01.
  Note
t  Vehicles with diesel engine and no auxiliary heater are currently fitted with an electric supplementary heater (heat energy is added to the air flow immediately after exiting from the heat exchanger of the air conditioner unit/heater) → Air conditioning; Rep. Gr.01 and → Heating; Rep. Gr.01.
t  A supplementary heating system is not available at present for vehicles with petrol engine.
t  On vehicles with diesel engine, the operating and display unit, Climatronic control unit -J255- (of the air conditioner/heater) actuates the auxiliary heater control unit -J364- by way of the convenience data bus system. This control unit then decides whether the auxiliary heater is to be activated as supplementary heater.
t  The following prerequisites must be met for the operating and display unit, Climatronic control unit -J255- to transmit a request for supplementary heater activation via the convenience data bus system:
–  Operating and display unit, Climatronic control unit -J255- switched on (OFF button not pressed)
–  ECON button not pressed (vehicles with air conditioner only)
–  Engine speed in excess of 600 rpm
–  Coolant temperature received via convenience data bus less than 70 °C (less than 80 °C at very low ambient temperatures)
–  Specified temperature calculated by operating and display unit, Climatronic control unit -J255- for air flowing out of passenger compartment vents greater than 45 °C (heating mode)
  A82-0355

  • Heating, ventilation, air conditioning system
  • Auxiliary heater
  • Self diagnosis, V.A.G Inspection Service
  • Auxiliary heater self-diagnosis

Technical data of self-diagnosis > < Connecting vehicle diagnostic tester