Electrically-Driven A/C Compressor, Flushing (Removing Refrigerant Oil)
Vehicles with a High-Voltage System (Hybrid Vehicles)
High voltage is extremely dangerous.
The high-voltage system is under high voltage. Electrocution can cause death or very serious personal injury.
-- Individuals with electronic/medical life and health sustaining machines in or on their person cannot perform any work on high-voltage systems. Some examples of life and health sustaining machines are 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 and hybrid vehicles an active ready mode is difficult to identify. Parts of the body can be pinched or pulled.
-- Switch 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 a high-voltage system, pay attention to the additional warnings for these vehicles. Refer to WARNINGS WHEN WORKING ON VEHICLES WITH HIGH VOLTAGE SYSTEM .
- If procedures are necessary near components of the high-voltage system, "visually inspect the high-voltage components and lines for damage". Refer to PERFORMING A VISUAL INSPECTION OF DAMAGE TO HIGH VOLTAGE COMPONENTS AND CABLES .
- If work on the high-voltage system components is necessary, de-energize the high-voltage system. Refer to the appropriate service information.
-- Charge the vehicle batteries, 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 BATTERY, CHARGING and the appropriate service information. .
-- 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.
Also move the selector lever into position "P" and activate the parking brake for testing and measuring procedures that 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-).
General notes to remove the refrigerant oil from the electrically driven A/C compressor (by flushing).
Electrically driven A/C compressors cannot have the refrigerant oil poured out in the same manner as a mechanically driven A/C compressor. There is no drain plug and because it is installed inside defending on the version only a specialized part or no refrigerant oil can be poured out. Depending on the version and the storage of the A/C compressor there remains when pouring our approximately 30 to 80 cm 3 refrigerant oil in the A/C compressor (the electrically driven A/C compressor cannot be turned). For this reason, the A/C compressor is to be flushed to remove the refrigerant oil and to determine the amount of refrigerant oil in the A/C compressor, depending on the complaint. Refer to COMPRESSOR, REPLACING WITHOUT THE NEED FOR FLUSHING REFRIGERANT CIRCUIT .
The refrigerant oil can be removed by flushing in the flow direction for electrically driven A/C compressors (because of the installed valve it is not possible to flush against the flow direction).
To flush, arrange the A/C compressor so that the connection for the refrigerant line on the high pressure side is as low as possible.
- The electrically driven A/C compressor is to be flushed when, there is dirt, too much refrigerant oil is in the refrigerant circuit, or is contaminated (with moisture debris) and to remove refrigerant oil from the A/C compressor. In these cases the refrigerant circuit must also be flushed, so that it will be cleaned and the correct refrigerant oil quantity for the refrigerant circuit can be set. Refer to REFRIGERANT OIL CAPACITIES .
- If the electrically driven A/C compressor is replaced, it is not always necessary to flush the coolant circuit. The amount of refrigerant oil found in the removed A/C compressor can be removed by flushing the A/C compressor. Pour the refrigerant oil out of the new A/C compressor so that only the amount remains (plus 10 cm 3 ) as before the old A/C compressor was flushed out. Refer to COMPRESSOR, REPLACING WITHOUT THE NEED FOR FLUSHING REFRIGERANT CIRCUIT .
- To remove the refrigerant oil from the removed A/C compressor the refrigerant oil must be flushed from the replaced A/C compressors and the removed amount measured (Empty the used oil collection from the A/C service station before flushing). Pour the refrigerant oil out of the new A/C compressor so that only the amount or refrigerant oil remains (plus 10 cm 3 ) in the new A/C compressor as the amount of flushed out refrigerant oil from the old A/C compressor. Dispose of the refrigerant oil removed from the defective and the new A/C compressor and poured out refrigerant oil from the new A/C compressor. Refer to Audi ServiceNet, HSO Environment (pay attention to local regulations).
- If not enough refrigerant oil can be poured out from the A/C compressor to be installed, flush the new A/C compressor. Fill the A/C compressor to be installed in after flushing with as much new refrigerant oil as was flushed from the removed A/C compressor. Example: 120 cm 3 of refrigerant oil was flushed out of the removed A/C compressor and there is 200 cm3 in the new A/C compressor to be installed (refer to the type plate and REFRIGERANT OIL CAPACITIES ). 110 cm3 (120 cm3 minus 10 cm3 ) must be poured out of the A/C compressor to be installed so that the amount of refrigerant oil in the refrigerant circuit after installing is correct. If the required amount of refrigerant oil cannot be poured out, flush the A/C compressor to be installed. In the new A/C compressor as much refrigerant oil is to be filled as was flushed out of the old A/C compressor.