Audi 100 1991 ➤ , Audi 80 1992 ➤ , Audi A1 2011 ➤ , Audi A1 Sportback 2 ...
Air conditioner with refrigerant R134a - Edition 11.2018
6
Problems with refrigerant circuit
⇒ “6.1 Possible complaints about refrigerant circuit”, page 185
6.1
Possible complaints about refrigerant
circuit
⇒ “6.1.1 Test requirements:”, page 185
⇒ “6.1.2 Possible complaints”, page 185
6.1.1
Test requirements:
•
Electrical system, vacuum system and air duct fault-finding
has not revealed any faults ⇒ Vehicle diagnostic tester (“Self-
diagnosis” or “Guided Fault Finding” function for air condition‐
er), ⇒ Current flow diagrams, Electrical fault finding and Fitting
locations and ⇒ Heating, air conditioning or ⇒ Air condition‐
ing .
•
Air conditioner self-diagnosis/Guided Fault Finding with the ⇒
Vehicle diagnostic tester has not revealed any faults, no com‐
pressor shut-off criteria displayed in measured value block
(vehicles with “air conditioner” self-diagnosis only) ⇒ Heating,
air conditioning or ⇒ Air conditioning or “Guided Fault Finding”
function ⇒ Vehicle diagnostic tester .
6.1.2
Possible complaints
Note
♦ For all complaints marked *, refer to ⇒ page 193 “Checking
pressures”.
♦ If problems are only encountered at one evaporator on vehi‐
cles fitted with two evaporators, also check the pressures in
the refrigerant circuit.
♦ Observe test requirements ⇒ page 185 .
Vehicles without high-voltage system
♦ The cooling system has failed completely.*
♦ Insufficient cooling output at all vehicle speeds/engine
speeds.*
♦ No or insufficient cooling after driving a few miles. *
♦ No or insufficient cooling at one or via both evaporators (on
vehicles with two air conditioning units). *
♦ Air conditioner compressor, air conditioning system magnetic
clutch - N25- or air conditioner compressor regulating valve -
N280- are shut off by a pressure switch (e.g. -F73-, -F118-, -
F129- or by the operating and display unit for front air
conditioning system - E87- or the Climatronic control unit -
J255- ) on account of excessive or inadequate pressure. * ⇒
Heating, air conditioner; Rep. gr. 87 ; Refrigerant circuit (ve‐
hicle-specific Workshop Manual).
♦ Fresh air supply is not available or is reduced significantly after
driving several miles (evaporator iced up). *
Vehicles with high-voltage system
♦ The cooling system has failed completely.*
♦ Insufficient cooling output at all vehicle speeds/air conditioner
compressor speeds.*
6. Problems with refrigerant circuit
185
English 
