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Electrical checks on components actuated by operating and display unit, Climatronic control unit J255 > < Test step "7”

A4 Mk2

Test step “8”
Test step “8”
Input for activation signal for actuation of operating and display unit, Climatronic control unit -J255- (e.g. from service installed auxiliary heater)
   
Vehicle diagnostic, testing and information system -VAS 5051A-, measurement mode: Multimeter, voltage measurement (20 VDC)
l  Adapter cable -V.A.G 1598/12- connected
Test stepTest box -V.A.G 1598A- socketChecking of
l  Test conditions
–  Additional operations
SpecificationMeasures to be taken if reading does not match specification
8.110
+
13		Input for activation signal tor operating and display unit, Climatronic control unit -J255-
l  Ignition off
t  Less than 2 V
–  Use current flow diagram to locate and eliminate short to positive

  Note
t  Only auxiliary heaters approved by Audi are suitable for service installation. Depending on version, these may be designed for data exchange with the operating and display unit, Climatronic control unit -J255- via the convenience data bus system (refer to corresponding installation instructions for auxiliary heater).
t  If, after switching off the ignition, the operating and display unit, Climatronic control unit -J255- remains in operation and the display in the measured value block, display group “022” is “1”, locate and eliminate short to positive to connector “D”, contact “10”.
t  Only genuine Audi auxiliary/supplementary heaters (depending on version) can also be actuated by way of the convenience data bus system and exchange data with the other control units linked to this bus system (refer to corresponding installation instructions for auxiliary heater).
t  The majority of commercially available auxiliary heaters cannot exchange data via the convenience data bus system. Such auxiliary heaters are not to be connected to the convenience data bus system.
   

Electrical checks on components actuated by operating and display unit, Climatronic control unit J255 > < Test step "7”