Audi Q5: Checking Pressures on Vehicles with Expansion Valve and Receiver/Dryer (with
Internally Regulated Compressor)
General Information
Note
- Connect the A/C service station. Refer to
→ Chapter "A/C Service Station, Connecting".
- Observe the test requirements. Refer to
→ Chapter "Pressures, Checking".
- With the ignition switched off, check the pressure in the
refrigerant circuit (using the service station). Refer to
→ Chapter "Refrigerant Circuit, Checking Pressure with Service
Station".
The pressures with the ignition turned off meet the
specifications.
- Start the engine.
- Bring the engine speed up to 2000 RPM.
- Observe the pressure gauge of the service station.
Note
- The switch pressures and design of refrigerant circuit
switches are vehicle-specific.
- Pressures must be measured at service connections; component
locations of these connections are vehicle-specific. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
Specified Values for the Refrigerant Circuit Pressures
High-Pressure Side:
Increasing from initial pressure (when connecting the
pressure gauges) to a maximum of 20 bar (290 psi).
Low-Pressure Side:
Decreasing from initial pressure (when connecting pressure
gauges) to the value in the graph.
A - High pressure in bar (psi)
B - Low pressure in bar (psi)
C - Permissible tolerance range
Note
If no malfunction can be found and air conditioner operation is not
OK when test is repeated, clean refrigerant circuit (flush using
refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blow through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen").
Note
If operation is not OK after cleaning refrigerant circuit (flushing
with R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blowing through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen"), expansion valve must be replaced.
Note
- It is not initially necessary to clean the refrigerant circuit
(flush using refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blow through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen") when this problem occurs since normally, there is
only a small quantity of moisture in the system which can be removed by
lengthy evacuation.
- If problem involving moisture in refrigerant circuit only occurs
after a lengthy operating period or only infrequently (low pressure
drops below specification and evaporator ices up), it is sufficient to
replace the dryer (adjust quantity of refrigerant oil). Refrigerant
circuit is then to be evacuated for at least three hours.
Note
If air conditioner operation is not OK when test is repeated,
install old expansion valve, clean refrigerant circuit (flush using
refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blow through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen"). Then replace the A/C compressor and
receiver/dryer.
Note
- If air conditioner operation is not OK when test is repeated,
install old expansion valve, clean refrigerant circuit (flush using
refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blow through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen"). Then replace the A/C compressor and
receiver/dryer.
- With this malfunction, evaporator may ice up although the quantity
of refrigerant in circuit is OK.
Note
- Overfilling with refrigerant oil can occur if, for example, the
compressor has been replaced without adjusting the quantity of
refrigerant oil.
- If there is too much refrigerant oil in the circuit, the compressor
must be drained and the receiver/dryer must be replaced. After cleaning
the refrigerant circuit (flushing with refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with Refrigerant
R134a"; or blowing through using compressed air and nitrogen.
Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen"), the correct quantity of refrigerant oil is filled
into the circuit. Refer to
→ Chapter "Approved Refrigerant Oils and Capacities".
READ NEXT:
Specified Values for the Refrigerant Circuit Pressures
Note
Connect the Air Conditioning (A/C) service station. Refer to
→ Chapter "A/C Service Station, Connecting".
Observe the test
General Information
Note
Connect the Air Conditioning (A/C) service station. Refer to
→ Chapter "A/C Service Station, Connecting".
Observe the test requirements. Refer to
→ C
General Information
Extremely Dangerous Due to High-Voltage
The high-voltage system is under high-voltage. Death or serious
bodily injury by electric shock.
- Individuals with electronic/medical
SEE MORE:
Special tools and workshop equipment
required
Pry Lever -80 - 200-
Trim Removal Wedge -3409-
Omega Clip Tool -T40280-, is needed to remove any clips are
that still inside the body.
Removing
- Versions with screen separator: Remove the screen separator.
- Fold the backrest forward.
-
Fig. 225 Right side of the cockpit: fuse panel with plastic
clip
Fuse panel A (black)
Steering column switch module
Terminal 15 diagnostic connector
Gateway (Databus diagnostic interface)
Auxiliary heater
Fuse panel B (brown)
CD /DVD player
Wi-Fi
MMI/Radio
Instrument cluster
Gateway (