Notes On Air Conditioner Self-Diagnosis - Audi Air conditioning 2003 A8 Workshop Manual

ing" function of vehicle diagnostic, testing and information
system VAS 5051 ).
– Ignition on and engine running
– Ambient temperature less than 20 °C
– Engine speed less than 2000 rpm
– Front operating and display unit, Climatronic control unit -
J255- switched on (
– Heat output requested for at least one side (driver or front
passenger side)
♦ The circulation pump -V55- is switched on as soon as all ac‐
tivation conditions are fulfilled. To stop the circulation pump
being constantly switched off and on, it remains activated for
at least 30 s even if - for example in the event of rapid changes
in vehicle speed - a request is only applied for a few seconds
(e.g. on accelerating after standing at traffic lights).
♦ For incorporation of the auxiliary/supplementary heater (and
circulation pump -V55- ) into the coolant circuit, refer to ⇒
Auxiliary/supplementary heater; Rep. gr. 82
2.2

Notes on air conditioner self-diagnosis

♦ There are different versions of the front operating and display
unit, Climatronic control unit -J255- and the rear Climatronic
operating and display unit -E265- . Pay attention to precise
assignment on replacement. ⇒ Electronic parts catalogue
♦ Air conditioner self-diagnosis is to be performed by way of the
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
„Guided fault-finding" function using the vehicle diagnostic,
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
testing and information system -VAS 5051 A- ⇒ "Guided fault-
with respect to the correctness of information in this document. Copyright by AUDI AG.
finding" function of vehicle diagnostic, testing and information
system VAS 5051.
♦ Front operating and display units can no longer be exchanged
in the familiar manner. Component protection is activated as
soon as a front operating and display unit, Climatronic control
unit -J255- has been matched to a vehicle. The component
protection feature can only be cancelled by entering certain
vehicle data ⇒ "Guided fault-finding" function of vehicle diag‐
nostic, testing and information system VAS 5051.
♦ If a front operating and display unit with active component
protection (anti-theft system) is installed in a different vehicle,
the functions required for vehicle security can still be selected,
but not the convenience functions ⇒ "Guided fault-finding"
function of vehicle diagnostic, testing and information system
VAS 5051.
♦ If a front operating and display unit, Climatronic control unit -
J255- (or the rear Climatronic operating and display unit -
E265- ) is to be replaced, interrogate the encoding (of the front
operating and display unit, Climatronic control unit -J255- ) and
the adaption (of the front operating and display unit, Clima‐
tronic control unit -J255- and the rear Climatronic operating
and display unit -E265- ) by way of the „Control unit replace‐
ment" function in the guided fault-finding routine for this oper‐
ating and display unit prior to removal ⇒ "Guided fault-finding"
function of vehicle diagnostic, testing and information system
VAS 5051.
♦ The „Electrical checks" function is not described in this Work‐
shop Manual. When implementing electrical checks by way of
the „Guided fault-finding" function, information is given on the
functions to be checked ⇒ "Guided fault-finding" function of
vehicle diagnostic, testing and information system VAS 5051.
♦ The temperature-dependent resistance values of the various
temperature sensors are stored in tables which can be called
button not pressed)
OFF
Audi A8 2003 ➤
Air conditioning - Edition 09.2010
2. Notes on general repairs
5