Audi Q5: A/C System, Operating after Charging
Note
- If the mechanically driven Air Conditioning (A/C) compressor
was removed, rotate it approximately 10 times by hand before
using it for the first time (during or after installing, for
example before installing the belt) to prevent damage caused by
liquid impact when first switched on (any oil in compressor
cylinder is forced out on rotation).
- If the electronically driven A/C compressor was removed,
activate it after filling the A/C compressor before the A/C
system on via the "basic setting, compressor cut-in" function
for the Guided Fault Finding. Use the Vehicle Diagnostic Tester
in the "Guided Fault Finding" Function for A/C System and
Battery Regulation. This prevents the A/C compressor from being
damaged, for example, by liquid impact when it is first switched
on (any oil in the A/C compression chamber is forced out).
- The vehicle engine drives the mechanically driven A/C
compressor via a belt or shaft. The electronically driven A/C
compressor is driven via an electric motor attached directly to
the A/C compressor (for example on hybrid vehicles).
Operating an A/C System with a Mechanically Driven A/C
Compressor
- Start engine with compressor switched off (version with A/C
clutch).
- Set compressor to minimum output, for example, "Econ" or A/C
off mode (version with no A/C clutch with regulating valve).
- Wait until idle speed has stabilized.
- Switch on the compressor and operate the system for at least
two minutes at idling speed.
- If necessary, check pressures in the refrigerant circuit
using the A/C service station.
- Turn the engine off.
- Screw out the hand wheel on the quick-release coupling
adapter.
- Disconnect the charging hoses from the refrigerant circuit.
- Install the caps.
Operating an A/C System with an Electrically Driven A/C
Compressor
- Operate the A/C compressor using "basic setting, compressor
cut-in" in Guide Fault Finding. Use the Vehicle Diagnostic
Tester"Guided Fault Finding" A/C System and Battery Regulation.
Additionally on vehicles with an electric operated valves in
the refrigerant circuit, which cannot be opened without power
(for example the Audi Q7 e-tron):
- Via the Vehicle Diagnostic Tester the electrically activated
valves which do not open without power for the operation of the
A/C system enable the activation of these valves via the
respective control module (to open or close) using the Vehicle
Diagnostic Tester in the "Guided Fault Finding" function.
Note
On vehicles with high-voltage system and additional
functions of the A/C system ("heat pump operation" or "cooling
the high-voltage battery") valves may be installed in the
refrigerant circuit which cannot be opened without power. These
valves are opened and closed for example via a step motor and
after switching off the ignition are no longer activated. To
completely drain, correctly discharge and charge the refrigerant
circuit no areas may be closed, for this reason the valves must
be opened before these procedures. After finishing work on the
activation of these valves are enabled via the respective
control module. Refer to
→ Heating, Ventilation and Air Conditioning; Rep.
Gr.87; Refrigerant Circuit; System Overview - Refrigerant
Circuit and using the Vehicle Diagnostic Tester in
the "Guided Fault Finding" function.
All
- After the basic setting and If necessary, check pressures in
refrigerant circuit using A/C service station. Refer to
→ Chapter "A/C Service Station, Connecting for Measuring and
Testing".
- Screw out the hand wheel on the quick-release coupling
adapter.
- Disconnect the charging hoses from the refrigerant circuit.
- Install the caps.
Refrigerant to Service Station Reservoir (Charging Cylinder or
Reservoir Bottle), Transferring
- The work procedure is always to be performed as described in
the operating instructions for the Air Conditioning (A/C)
service station.
- A certain quantity of refrigerant is specified as charge for
each air conditioning system. To ensure that neither too much
nor too little refrigerant is added (either would reduce the
cooling output), the charging cylinder has a scale indicating
the weight.
- The volume of a refrigerant changes as a function of
pressure. The scale must therefore be set according to the
pressure in the charging cylinder.
Note
Do not completely drain the reservoir (charging cylinder or
bottle) as the liquid column boundary layer cannot be traced in
the tube during filling (outside visible range).
WARNING
Do not overfill. A completely filled reservoir
(charging cylinder or bottle) will explode when the
temperature rises.
Service Station, Draining
Note
- If it is necessary to drain the service station (for
example, due to extraction of contaminated refrigerant), all
filters and dryers must always be replaced (do not remove filter
and dryer from the air-tight packaging until immediately before
installation to minimize moisture absorption).
- Refrigerant containers filled with contaminated used
refrigerant are referred to as "Recycling containers".
- Thoroughly evacuate the recycling containers prior to
initial filling with refrigerant (if there is air in a
refrigerant container it is not to be filled with refrigerant).
- Different types of refrigerant may not be mixed together
(refrigerant mixtures cannot be recycled and are to be disposed
of). If there is any doubt about the composition of the contents
of the container, the refrigerant recycling company is to be
informed accordingly.
Caution
- When filling recycling containers (compressed-gas
containers), observe applicable regulations, technical
rules and laws.
- Recycling containers are never to be overfilled.
Overfilled containers do not have a sufficient gas
cushion to accommodate the liquid expansion caused by
the effects of heat. There is a danger of rupture.
- To ensure safety, make exclusive use of recycling
containers fitted with a safety valve.
- Recycling containers must be weighed on calibrated
scales during the filling process. The maximum
permissible capacity is 75% (charge factor 0.75) of the
charge weight indicated on the recycling container (the
possibility of refrigerant oil entering the recycling
container along with the refrigerant cannot be ruled
out).
READ NEXT:
Possible Refrigerant Circuit Concerns
Test Requirements
Electrical Equipment, vacuum system and air duct
fault-finding has not revealed any faults. Refer to Guided Fault
Finding for the A/C system
Vehicles with a High Voltage System (Hybrid Vehicles)
Extremely Dangerous Due to High-Voltage
The high-voltage system is under high-voltage. Death or serious
bodily injury by electric shock.
- I
SEE MORE:
Special tools and workshop equipment
required
Torque Wrench 1332 40-200Nm -VAG1332-
Track Rod Tool Insert -T40183-
No illustration, commercially available pawl with fine gear
Removing
- Determine dimension -a- from
the center of the wheel to the lower edge of the wheel housing
before st
Component Location Overview - Passenger Occupant Detection System
WARNING
The replacement part (service kit) for the passenger
occupant detection system is already precalibrated and must not
be separated under any circumstances. The service kit consists
of:
Passive Occupant Detection S