Audi A4: Compressor, Replacing on Account of Leakage or Internal Damage
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.
- Individuals with electronic/medical life- and health sustaining
machines in or on their person cannot perform any work on high-voltage
systems. Life- and health sustaining machines are for example pain
killer pumps, implanted defibrillators, pacemakers, insulin pumps, and
hearing aids.
- Have the high-voltage system de-energized by a qualified person.
There is a Risk of Injury from the Engine Starting Unexpectedly
On electric - hybrid vehicles an active ready mode is difficult to
identify. Parts of the body can be clamped or pulled.
- Turn off the ignition.
- Place the ignition key outside of the vehicle interior.
Risk of Damaging the High-Voltage Cables
Misuse can damage the insulation of high-voltage cables or
high-voltage connectors.
- Never support objects on the high-voltage cables and the
high-voltage connectors.
- Never support tools on the high-voltage cables and the high-voltage
connectors.
- Never sharply bend or kink the high-voltage cables.
- When connecting pay attention to the coding of the high-voltage
connectors.
- For all procedures on vehicles with high-voltage system pay
attention to the additional warning message for these vehicles.
Refer to
→ Chapter "Warnings when Working on Vehicles with High Voltage
System".
- If procedures are necessary near components of the
high-voltage system "perform a visual inspection of the damage
of the high-voltage components and lines". Refer to
→ Chapter "Performing a Visual Inspection of Damage to High
Voltage Components and Cables".
- If work on the components of the high-voltage system is
necessity, de-energize the high-voltage system. Refer to
→ Rep. Gr.93; High-Voltage System, De-Energizing or
→ Electrical Equipment; Rep. Gr.93; High-Voltage System,
De-Energizing.
- Charge the vehicle battery, for example, using the Battery
Charger -VAS5904- in the battery support mode to minimize the
number of automatic starts during the test- and measuring
procedures while the ready mode is active. Refer to
→ Electrical Equipment General Information; Rep. Gr.27; Battery;
Battery, Charging and
→ High Voltage Vehicle General Information; Rep.
Gr.93; High-Voltage System General Warnings.
- For testing and measurement procedures that require the
ready mode to be active or the ignition to be switched on, the
selector lever must be in the "P" position and the parking brake
must be activated. The required tools must be placed so that
they do not come into contact with any rotating components in
the engine and they must also not go into the vicinity of the
rotating components when the engine is running.
Note
- Also move the selector lever into position "P" and activate
the parking brake for testing and measuring procedures which
require the ignition to be on, but do not require the ready mode
to be active.
- The ready mode is displayed in the Instrument Cluster
Control Module -J285- above the "power meter". Refer to Owner's
Manual.
- For activating and deactivating the ready mode, refer to the
Owner's Manual (while doing so, note the display in the
Instrument Cluster Control Module -J285-).
All Vehicles
For example, because of noise or no A/C compressor output
Note
- If there is damage on the A/C compressor electronics, for
example on the A/C Compressor Regulator Valve -N280- on a
mechanically driver A/C compressor or the A/C Compressor Control
Module -J842- of the electrically driven A/C compressor the
refrigerant circuit does not have to always be cleaned. Here it
is usually acceptable to replace the A/C compressor without
cleaning the refrigerant circuit (adapt the amount of
refrigerant oil). Refer to
→ Chapter "Compressor, Replacing without the Need for Flushing
Refrigerant Circuit".
- If a faulty A/C compressor is replaced with an A/C
compressor from another manufacturer check for the A/C
compressor to be installed has the same refrigerant oil approved
which is already in the refrigerant circuit (from the removed
A/C compressor). If a different refrigerant oil is approved for
the A/C compressor to be installed then the A/C compressor which
was removed, the refrigerant circuit must be flushed. Refer to
→ Chapter "Approved Refrigerant Oils".
- Discharge the refrigerant circuit.
- Remove the A/C compressor. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; A/C
Compressor (vehicle-specific repair manual).
- Clean the refrigerant circuit (flush with Refrigerant
R134a). Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with
Refrigerant R134a" .
Note
- For internal damage (to the A/C compressor) check the
refrigerant hoses and condenser for example shavings have
penetrated clean refrigerant hoses and condenser (flush with
refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with
Refrigerant R134a" and if necessary replace the
refrigerant hoses.
- In vehicles with two evaporators, the refrigerant oil
quantity in refrigerant circuit may be greater than the quantity
which is found in the replacement compressor, if necessary add
the remaining refrigerant oil quantity to the refrigerant
circuit. Refer to
→ Chapter "Refrigerant Circuit, Flushing with Compressed Air and
Nitrogen".
- Replace the dryer cartridge, receiver/dryer, or reservoir,
and restrictor. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
- Examine the expansion valve for dirt or corrosion; replace
if necessary. Refer to
→ Heating, Ventilation and Air Conditioning; Rep. Gr.87; System
Overview - Refrigerant Circuit (vehicle-specific
repair manual).
- Assemble, evacuate and charge the refrigerant circuit.
READ NEXT:
Note
Cleaning the refrigerant circuit means flushing it with
refrigerant R134a. Refer to
→ Chapter "Refrigerant Circuit, Cleaning (Flushing), with
Refrigerant R134a" or blowing throu
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 syste
Approved Refrigerant Oils and Capacities
Note
As PAG (polyalkylene glycol) oil is highly hygroscopic
(attracts water), opened containers are to be immediately
resealed so as to be air-tigh
SEE MORE:
Fig. 96 Center console: shifting manually with the selector
lever
Fig. 97 Steering wheel: shift paddles*
You can shift the gears manually when in "D"
mode. The transmission is in tiptronic mode and
"M" is displayed in the instrument cluster. You
can shift into manual shifting mode while the vehicl
Applies to: vehicles with vehicle jack
Fig. 174 Sill panels: markings
Fig. 175 Sill: positioning the vehicle jack
Place the vehicle jack from the vehicle tool kit
on a firm surface. Use a flat, stable support if
necessary. On a slippery surface such as tile,
you should use a non-slip pad such