Audi Q5: A/C Compressor Regulator Valve -N280-, Removing and Installing
Note
- Certain functions on the A/C Compressor Regulator Valve
-N280- (for example, a stuck valve or a disruption in the coil)
can lead to a complaint regarding the A/C compressor (A/C system
doesn't cool, the evaporator ices over, etc.). If the cause is
with the A/C Compressor Regulator Valve -N280- (and not the A/C
compressor itself), the A/C compressor can be serviced by
replacing the A/C Compressor Regulator Valve -N280--C
and D-.
- The A/C Compressor Regulator Valve -N280--C
and D- is not available as a replacement part for all A/C
compressors. If the A/C Compressor Regulator Valve -N280- is not
available as an individual A/C compressor part, then the entire
A/C compressor must be replaced. Refer to the Parts Catalog.
- The A/C Compressor Regulator Valve -N280- is available in
different versions and settings. Refer to the Parts Catalog. On
the A/C compressor -A- (shown is an
A/C compressor manufactured by "Denso" without an A/C Clutch
-N25-), the connector for the vehicle wiring harness connection
is attached with a short wiring harness to the A/C Compressor
Regulator Valve -N280--C-. On the
A/C compressor -B- (shown is an A/C
compressor manufactured by "Sanden"), the connector for the
vehicle wiring harness connection is mounted directly on the A/C
Compressor Regulator Valve -N280--C-.
The removal and installation of the A/C Compressor Regulator
Valve -N280--C and D- on other A/C
compressors (other type and manufacturer) is basically the same
and only slightly deviates from the procedure described below.
- The A/C Compressor Regulator Valve -N280- is available in
different versions and settings. Refer to the Parts Catalog. On
an A/C Compressor with an A/C Clutch -N25- (shown is an A/C
compressor manufactured by "Denso"), the connector for the
vehicle wiring harness connection is mounted directly on the A/C
Compressor Regulator Valve -N280--A-.
On another A/C compressor, the connector for the vehicle wiring
harness connection is combined in a 3-pin connector
-E- for the A/C Clutch -N25- and
the A/C Compressor Regulator Valve -N280-.
- For version -B- of the A/C
Compressor Regulator Valve -N280-, the wire connection may be
directly connected to the A/C Compressor Regulator Valve -N280-,
or there is an additional connector on the A/C Compressor
Regulator Valve -N280-.
- Removing and installing the A/C Compressor Regulator Valve
-N280--A and B- is essentially the
same on both versions. It only deviates slightly from the
procedure described below. On an A/C compressor with a 3-pin
connector -E-, disconnect the
respective wires to the A/C Compressor Regulator Valve -N280-
from the A/C Compressor Regulator Valve -N280-, remove from the
connector -E- or cut at a suitable
location (and reattach using wire connectors from the Wiring
Harness Repair Set -VAS1978B-).
- If the A/C Compressor Regulator Valve -N280- malfunction was
found to be caused by dirt, shavings or abraded A/C compressor
material after the removal of the A/C Compressor Regulator Valve
-N280-, clean the refrigerant circuit and replace the A/C
compressor. Refer to
→ Chapter "Compressor, Replacing on Account of Leakage or
Internal Damage" and
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with
Refrigerant R134a".
Removing
- Discharge the refrigerant circuit. Refer to
→ Chapter "Using Service Station".
Caution
There is a risk of damaging the A/C compressor if
the refrigerant circuit is empty.
Do not start the motor if the refrigerant circuit is
empty.
- Depending on the version of the A/C Service Station,
the pressure of the refrigerant circuit may be less than
1 bar (14.5 psi) absolute pressure after it has been
discharged.
- Depending on the version of the A/C compressor, it
may be damaged if the pressure in the refrigerant
circuit is too low.
- Do not start the engine while the refrigerant
circuit pressure is less than the ambient pressure.
- Depending on the vehicle and installed location of the A/C
compressor, remove the components that prevent access to the A/C
Compressor Regulator Valve -N280-. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
On vehicles where at least one of the two refrigerant lines
and the A/C Compressor Regulator Valve -N280- cannot be
disconnected and removed while the A/C compressor is attached to
the engine.
- Remove the A/C compressor. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; A/C
Compressor (vehicle-specific repair manual).
Note
A refrigerant line must be removed on an installed A/C
compressor so that it is assured, that the pressure in the A/C
compressor is the same as the ambient pressure.
On a vehicle, where at least one of the two refrigerant
lines and the A/C Compressor Regulator Valve -N280- can be
disconnected and removed while the A/C compressor is attached to
the engine (the A/C compressor is not removed).
WARNING
There is a danger of ice-up.
- Before removing the A/C Compressor Regulator Valve
-N280-, connect the service station and extract the
refrigerant. Refrigerant circuit must be empty to avoid
possible injury.
- Refrigerant and refrigerant oil will leak out if the
refrigerant circuit is not discharged.
- The refrigerant is extracted before removing the A/C
Compressor Regulator Valve -N280-. If the A/C Compressor
Regulator Valve -N280- is not removed within 10 minutes
after extraction, pressure may build up in the
refrigerant circuit by renewed evaporation. Extract the
refrigerant once more.
- Check the pressure in the refrigerant circuit once more via
the A/C service station pressure gauge.
- If the displayed pressure is larger than the ambient
pressure (larger than approximately 1 bar (14.5 psi) absolute
pressure), turn on the A/C service station and extract the
refrigerant that is building up the pressure.
- Disconnect one of the two refrigerant lines from the A/C
compressor. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
Note
A refrigerant line must be removed on an installed A/C
compressor so that it is assured, that the pressure in the A/C
compressor is the same as the ambient pressure.
All vehicles
- Before removing the A/C Compressor Regulator Valve -N280-
check again if the A/C compressor is actually being driven by
the belt pulley/drive unit. If the belt pulley or the drive unit
overload protection has triggered, the cause for the fault is
not the regulator valve but rather the A/C compressor (for
example does not move easily).
Note
- This illustration shows the A/C Compressor Regulator Valve
-N280--B- on a A/C compressor
manufactured by "Sanden" type "PXE 14". On these A/C compressors
the connector to the vehicle wiring harness connection is
mounted directly on the A/C Compressor Regulator Valve -N280--B-.
The removal and installation of the A/C Compressor Regulator
Valve -N280--B- on other A/C
compressors (other type and manufacturer, for example "Denso",
the A/C Compressor Regulator Valve -N280- with a short wiring
harness, for example) can differ. The procedure for removal and
installation is however the same, as described in the following
for the A/C compressor manufactured by "Sanden" type "PXE 14".
- This illustration shows an A/C Compressor Regulator Valve
-N280--B- with an O-ring
-E- (not available on all
versions).
- On a A/C Compressor Regulator Valve -N280--B-
without an O-ring -E-, dirt can
penetrate into the A/C Compressor Regulator Valve -N280--C-
mount up to the O-ring -F-.
- If applicable, loosen the wire connection from the A/C
Compressor Regulator Valve -N280--B-
to the connection to the vehicle wire harness from the A/C
compressor.
Note
- On an A/C compressor with an A/C Clutch -N25- where the A/C
Clutch -N25- is activated via the same connector as the A/C
Compressor Regulator Valve -N280--B-,
remove the applicable wires from the connector (for example,
using an extractor from the Wiring Harness Repair Set
-VAS1978B-). Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
- If a connector should be installed on an A/C compressor with
an A/C Clutch -N25- where the wires cannot be removed, cut the
wires to the A/C Compressor Regulator Valve -N280- (or to the
A/C Clutch -N25-) at a suitable location and reattach using wire
connectors from the Wiring Harness Repair Set -VAS1978B- (or
replace the connector itself. Refer to the Parts Catalog). Refer
to
→ Electrical Equipment; Rep. Gr.97; Connectors; Wiring Harnesses
and Connectors, Repairing.
- Clean the A/C compressor near the circlip
-A- and the A/C Compressor
Regulator Valve -N280--B-
thoroughly.
Caution
The pressure in the A/C compressor must be equal to
the ambient pressure.
- Refrigerant and refrigerant oil can leak out if
there is excess pressure in the A/C compressor.
- Dirt can be absorbed into the A/C compressor if
there is a vacuum in the A/C compressor.
- Make sure there is pressure equalization before
removing the A/C Compressor Regulator Valve -N280--B-.
- Remove the circlip -A-.
- Carefully remove the A/C Compressor Regulator Valve -N280--B-
from the A/C compressor mount -C-,
using a suitable screwdriver -D-,
for example.
- Check the removed A/C Compressor Regulator Valve -N280--B-
and A/C compressor mount -C- for
dirt.
Note
- If the strainer -D-, A/C
Compressor Regulator Valve -N280--B-
up to the O-ring -F- or the A/C
compressor mount -C- are heavily
contaminated in this area (with shavings or dark, sticky abraded
material, for example), this indicates damage on the A/C
compressor. In this case, the refrigerant circuit is to be
cleaned and the A/C compressor is to be replaced. Refer to
→ Chapter "Compressor, Replacing on Account of Leakage or
Internal Damage" and
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with
Refrigerant R134a".
- If the strainer -D- on the A/C
Compressor Regulator Valve -N280--B-
and the A/C compressor mount -C- up
to the O-ring sealing surface -F-
are only lightly contaminated in this area (with gray deposits
from normal A/C compressor operation, for example), a
malfunction at the A/C Compressor Regulator Valve -N280--B-
can cause the A/C compressor malfunctioning.
- On an A/C Compressor Regulator Valve -N280--B-
without an O-ring -E-, dirt can
penetrate into the mount -C- up to
the O-ring -E- during operation.
Remove the dirt carefully and completely using, for example, a
lint-free cloth (do not work with compressed air).
Installing
- Check the A/C compressor mount -C-
and the circlip groove for dirt, and if necessary, clean them
carefully and thoroughly with a clean, lint-free cloth.
Caution
Danger of another A/C Compressor Regulator Valve
-N280--B- or A/C compressor
failure due to dirt in the A/C compressor or damage to
the sealing surfaces in the mount.
- If necessary, carefully clean the A/C compressor
mount -C- using only a
clean, lint-free cloth (do not use compressed air).
- Make sure while cleaning the mount
-C- that no dirt gets into
the area underneath the O-ring sealing surface
-F- or the existing
channels and none of the mount sealing surfaces become
damaged.
- Check the A/C compressor mount -C-
for damage (also pay attention to small scratches on the
surface, if there is damage, replace the A/C compressor).
- Check the O-rings -F,G and H-
and -E- (if applicable) of the A/C
Compressor Regulator Valve -N280--B-
for damage.
- Coat the O-rings -F, G and H-
and -E- (if applicable) of the A/C
Compressor Regulator Valve -N280--B-
lightly with refrigerant oil and check for proper seating.
- Insert the A/C Compressor Regulator Valve -N280--B-
until the stop in the A/C compressor mount
-C-.
- Install the new circlip -A- and
check for proper seating in the groove.
- Install the removed parts in the opposite order.
- Evacuate and refill the refrigerant circuit. Refer to
→ Chapter "Using Service Station".
Note
Should refrigerant oil escape with the A/C Compressor
Regulator Valve -N280--B- removed,
add this amount of refrigerant oil while filling the refrigerant
oil with the A/C service station. Refer to
→ Chapter "Using Service Station".
- Check the A/C function. Refer to
→ Chapter "Pressures, Checking" and
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
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Note
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Testing Equipment, Tools and Materials
General Information
Note
This list outlines the testers, tools and materials required
for expert refrigerant circuit repair work.
For tools and materi
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Fig. 23 Display: Danger symbol
With a priority 1 malfunction, a red symbol appears in the upper center area
of the display > fig. 23. A driver message appears as well to ex plain the
malfunction in more detail. When this symbol appears, three warning tones sound
in succession. The symbol co
Overview - Rear Window
1 - Rear Window
2 - Adhesive Bead
Note
Note varying spacing dimensions to window edge.
Dimension -a- = 11 mm.
Dimension -b- = 12.5 mm.
Dimension -c- = 15.5 mm.
3 - Roof Spoiler
Removing and Installing. Refer to
→ Chapter "O