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Display groups not used at present for service purposes > < Display group "125”

A4 Cabriolet Mk2

Display group “126”
Display group “126”
Information from auxiliary heater control unit -J364- and convertible top operation control unit -J256- and information on operating status of convenience data bus system
   
Display zoneSignificanceExplanatory notes
1Information from auxiliary heater control unit -J364-
t  Display = “Aux. heat. 0”
–  Messages from auxiliary heater control unit -J364- not being received
–  Genuine Audi auxiliary/supplementary heater not fitted as optional extra
t  Display = “Aux. heat. 1”
–  Messages from auxiliary heater control unit -J364- being received
l  Data are transmitted by way of the convenience data bus system
l  The auxiliary heater control unit -J364- is attached to the auxiliary heater.
l  If the display is “0” on vehicles with genuine Audi auxiliary/supplementary heater, interrogate fault memory → Chapter and check convenience data bus system → Chapter
–  The display can be ignored for vehicles with no genuine Audi auxiliary/supplementary heater.

  Note
t  Only genuine Audi auxiliary/supplementary heaters can be actuated by way of the convenience data bus system and exchange data with the other control units linked to this bus system.
t  The majority of commercially available auxiliary heaters cannot exchange data via the data bus system. Such auxiliary heaters are not to be connected to the data bus system.
   
Display zoneSignificanceExplanatory notes
2Information from convertible top operation control unit -J256-
t  Display = “Convertible top 0”
–  Messages from convertible top operation control unit -J256- not being received
–  This display can be ignored if applicable for Saloon, Avant and Coupe (control unit is only fitted on Cabrio)
t  Display = “Convertible top 1”
–  Messages from convertible top operation control unit -J256- being received
l  Data are transmitted by way of the convenience data bus system
l  If “0” is displayed for Cabrio, interrogate the fault memory → Chapter and check the convenience data bus system → Chapter
–  If applicable, check and correct encoding of operating and display unit, Climatronic control unit -J255- on Saloon, Avant and Coupe.
 
t  Display = n. fitted
l  The operating and display unit, Climatronic control unit -J255- has been encoded for a vehicle with no convertible top (Saloon, Avant or Coupe). If applicable, check encoding of operating and display unit, Climatronic control unit -J255- → Chapter.

  Note
t  With the Audi Cabrio, different settings are stored for closed and open convertible top in the operating and display unit, Climatronic control unit -J255-. On opening and closing the convertible top, the operating and display unit, Climatronic control unit -J255- then automatically alters the setting to the value last set with convertible top closed or open.
t  As of Model Year 2003, operating and display units, Climatronic control unit -J255- with part number index “H” onwards (with software version as of “XX16”) have gradually been installed. This operating and display unit, Climatronic control unit -J255- differs as follows from the model with software version “XX15”:
t  - Modified passenger compartment temperature regulation for Audi Cabrio and open convertible top (designed to be somewhat cooler)
t  - Extended temperature adjustment range; 16 °C (instead of 18 °C) is now the lowest temperature which can be set → Parts List
   
Display zoneSignificanceExplanatory notes
3Display zone not used
–  Operating and display unit, Climatronic control unit -J255- with part number index up to “G” (up to software version “XX14”) and index “AJ” onwards
 
 Information from control unit in dash panel insert -J285-
–  Operating and display unit, Climatronic control unit -J255- with part number index “H” onwards (as of software version “XX15”) up to index “AH”
t  Display = “Voice 0”
–  No telephone hands-free unit fitted in vehicle and “telephone operation voice recognition” module thus not transmitted.
–  Telephone hands-free unit fitted in vehicle, however adaption of appropriate control units not implemented as specified.
–  Telephone hands-free unit fitted in vehicle, “telephone operation voice recognition” module not transmitted or received since switching on ignition.
t  Display = “Voice 1”
–  Telephone hands-free unit fitted in vehicle, “telephone operation voice recognition” module received.
l  Data are transmitted by way of the convenience data bus system
l  If “0” is displayed for vehicles with telephone hands-free unit, start up telephone with hands-free unit if applicable. If display does not change:
–  Interrogate fault memory → Chapter.
–  Check adaption of control unit in dash panel insert -J285- and telephone/telematics control unit -J526- → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051 and → Electrical system; Rep. Gr.01
–  Check convenience data bus system → Chapter.

  Note
t  This display zone indicates that the message received by the control unit in dash panel insert -J285- by way of the convenience data bus system contains a module for the “telephone operation voice recognition” function.
t  The information “telephone operation voice recognition” is currently only transmitted for vehicles with a factory-fitted telephone hands-free unit. Depending on the vehicle version, the information may however only be transmitted if the voice input button has been pressed at least once or the telephone used at least once since switching on the ignition.
t  Depending on the version of the operating and display unit, Climatronic control unit -J255-, the information “Voice 1” is only displayed whilst information is actually being received via the convenience data bus system.
   
Display zoneSignificanceExplanatory notes
4Operating status of convenience data bus system
t  Display = “two-wire”
–  Convenience data bus system in two-wire mode (normal status)
–  Reception of information transmitted on convenience data bus system at both inputs (“Can-Hi” and “Can-Lo”)
t  Display = “one-wire”
–  Convenience data bus system in one-wire mode (emergency operation)
–  Reception of information transmitted on convenience data bus system at one input only (“Can-Hi” or “Can-Lo”)
l  Data are transmitted on the convenience data bus system via two signal wires.
–  If “one-wire” is displayed, interrogate the fault memory → Chapter and check the convenience data bus system → Chapter

  Note
t  In contrast to the drive data bus system, the convenience data bus system can also operate in one-wire mode. However the system is then set to emergency operation.
t  If information is not received on the convenience data bus system, the operating and display unit, Climatronic control unit -J255- does not actuate the air conditioning system compressor regulating valve -N280- (compressor off).
   

Display groups not used at present for service purposes > < Display group "125”