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Display group "012” > < Measured value blocks from display group "011” to display group "020”

A4 Cabriolet Mk2

Display group “011”
Display group “011”
Measured value of dash panel temperature sensor -G56-, measured speed of temperature sensor blower -V42-, coolant temperature transmitted by control unit in dash panel insert -J285- and actuation of output for idling speed increase
   
Display zoneSignificanceExplanatory notes
1Measured value of dash panel temperature sensor -G56- in ° C
l  Installed in operating and display unit, Climatronic control unit -J255-
–  The operating and display unit, Climatronic control unit -J255- is fitted with a temperature sensor blower -V42-, which is responsible for blowing air from the central dash panel area to the dash panel temperature sensor -G56-
2Speed of temperature sensor blower -V42- in rpm
t  Display = greater than 2000
–  Blower speed OK
t  Display = less than 2000
–  Temperature sensor blower -V42- stiff, replace operating and display unit, Climatronic control unit -J255-
l  Installed in operating and display unit, Climatronic control unit -J255-
–  The operating and display unit, Climatronic control unit -J255- is fitted with a temperature sensor blower -V42-, which is responsible for blowing air from the central dash panel area to the dash panel temperature sensor -G56-.

  Note
t  The dash panel temperature sensor -G56- is vented by the temperature sensor blower -V42-. If the intake frame in the trim of the operating and display unit, Climatronic control unit -J255- is closed off or if the temperature sensor blower -V42- is not running, the temperature sensor cannot properly record the actual passenger compartment temperature and air conditioner regulation will not be correctly implemented.
t  The dash panel temperature sensor -G56- and the temperature sensor blower -V42- are permanently installed in the operating and display unit, Climatronic control unit -J255- and cannot be replaced separately.
t  The temperature sensor blower -V42- is always in operation when the ignition is on.
t  If the temperature sensor blower -V42- is stiff and the blower speed drops below 1500 rpm, this situation is stored as a fault in the fault memory of the operating and display unit, Climatronic control unit -J255-. At ambient temperature, the temperature sensor blower -V42- runs at a speed of approx. 3000 rpm.
   
Display zoneSignificanceExplanatory notes
3Coolant temperature in ° C transmitted by control unit in dash panel insert -J285-
l  Data are exchanged by way of the convenience data bus system.

  Note
t  To prevent abrupt shutoff of the compressor on account of excessive coolant temperature, its output is reduced by the operating and display unit, Climatronic control unit -J255- as soon as the coolant temperature transmitted by the control unit in dash panel insert -J285- exceeds 115° C (at 118° C the compressor is shut down completely).
t  If the coolant temperature is less than 40 °C, the control unit in dash panel insert -J285- may not transmit a coolant temperature by way of the convenience data bus system. In this case, start the engine and wait until the coolant temperature is in excess of 40 °C. If “Not OK” is displayed with a warm engine, perform self-diagnosis for the control unit in dash panel insert -J285- → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051 and → Electrical system; Rep. Gr. 01
   
Display zoneSignificanceExplanatory notes
4Actuation of output for idling speed increase
t  Display = “Off”
–  Idling speed increase not requested by operating and display unit, Climatronic control unit -J255-
t  Display = “On”
–  Idling speed increase requested by operating and display unit, Climatronic control unit -J255- (e.g. in “Lo” or “Hi” temperature setting)
l  Data are transferred via the convenience data bus system to the control unit in dash panel insert -J285-. The control unit in dash panel insert -J285- transmits the data via the drive data bus system to the engine control unit.

  Note
t  The way in which this signal is processed in the engine control unit varies for the individual engines.
t  Checking “Idling speed control” (idling speed increase) function → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051, → Ignition and injection system; Rep. Gr.01, → Diesel direct injection and glow plug system; Rep. Gr.01
t  Idling speed control is only activated if there are no compressor shutoff criteria preventing actuation of the air conditioning system compressor regulating valve -N280- (e.g. engine not running or “Econ” mode selected). The operating and display unit, Climatronic control unit -J255- activates the request e.g. in “Lo” or “Hi” temperature setting.
t  This function informs the engine control unit that the air conditioner requires a higher engine speed to attain the specified setting (higher compressor speed or more heat output from engine).
t  The request for idling speed increase is activated by the operating and display unit, Climatronic control unit -J255- to provide better heating or cooling output, e.g. in “Hi” or “Lo” temperature setting (“Lo” only with compressor switched on).
   

Display group "012” > < Measured value blocks from display group "011” to display group "020”