Volkswagen Tiguan Service and Repair Manual: Electrically Driven A/C Compressor, Flushing

Vehicles with a high voltage system

Observe all of the additional warnings for all work performed on vehicles with the high voltage system.

WARNING

Risk of unintended engine start

The ignition must be turned off and the ignition key must remain outside of the vehicle when working on vehicles with a high voltage system.

WARNING

Handling high voltage cables:

• Do not stand on or place tools on high voltage cables and their components as it may damage the cable insulation.
• Never bend or kink high voltage cables forcefully as it may damage the cable insulation.
• The round high voltage connectors are color coded with an external color ring and are mechanically coded using the guide- or code tabs. Always make certain that the coding matches when connecting the round connector in order to avoid any mechanical damage the high voltage connector.

WARNING

There is a risk of electrocution from damaged high voltage components.

Observe the following when working around high voltage components and high voltage wires:

• Never work around high voltage components and cables with cutting, deformed, or sharp edged tools, or heat sources such as welding or soldering tools, heated air, and thermal glue.
• Inspect the high voltage components visually before beginning.
• Perform a visual inspection of the Electric Drive Power and Control Electronics -JX1-, the Electro-Drive Drive Motor -V141-, the Electrical A/C Compressor -V470- and the high voltage lines when working in the engine compartment.
• Perform a visual inspection of the high voltage lines and covers when working on the underbody.
• Perform a visual inspection of the high voltage lines and the Electrobox with the High Voltage System Maintenance Connector -TW- when working in the luggage compartment.
• Perform a visual inspection on all of the potential equalization cables.

Observe the following items when performing the visual inspection:

• The components do not display any signs of external damage.
• The high voltage cable insulation and the potential equalization cables are not damaged.
• The high voltage cables do not display any abnormal deformations.
• Every high voltage component is marked with a red warning label.

If it is necessary to perform work in the vicinity of high voltage components, perform a "visual inspection" of the high voltage components and cables for damage and follow the "general warnings when working on the high voltage system".

If it is necessary to perform work on the high voltage components, disable the high voltage system.

Note

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.

If an electrically-driven A/C compressor is being replaced that does not have a mechanical fault (for example, a faulty circuit board), then determine how much refrigerant is in this A/C compressor.

Note

• This A/C compressor must be flushed to get all the refrigerant oil out.
• The A/C compressor is flushed in the flow direction (from the low pressure side input to the high pressure side output
• So that as much refrigerant oil as possible is flushed out of the A/C compressor, the A/C compressor must be positioned so that the high pressure side output is as low as possible.
• If an A/C service station without a flushing program is used, the procedure must be performed manually (evacuate, flush 3 times with at least 2 kg refrigerant each and extract refrigerant again, evacuate).

Quantity: for example 50 cm³

Pour so much refrigerant oil out of the new A/C compressor so that only the amount remains (plus 10 cm ³) that had been flushed out of the old A/C compressor beforehand. If the new original A/C compressor has for example, 200 cm³, then only pour out 140 cm³.

• Pour old refrigerant oil out of A/C compressor. Handling refrigerant oil.

Note

In not enough refrigerant oil can be poured out from the A/C compressor to be installed, flush the new A/C compressor. After flushing, fill the A/C compressor to be installed with as much new refrigerant oil as was flushed from the replaced A/C compressor.

1. A/C service station

Note

Flushing the A/C compressor is performed manually.

• Extract the refrigerant, if necessary.
• Empty the Service Station old oil container.

Note

On some Service Stations, the oil is first separated in the vacuum phase and then it goes into the old oil container.

• Set the amount of refrigerant on the Service Station to 2 kg and the oil quantity to 0.
• Set up the Refrigerant Circuit Flushing Device -VAS6336/1- or Air Conditioning Flush Tool -VAS6337/1A- between the A/C service station and refrigerant circuit return line.
• Evacuate the refrigerant circuit for 10 minutes. Then observe the vacuum display. If the vacuum remains constant, then fill the circuit with 2 kg refrigerant R134a. Then extract again and repeat the procedure one more time.

2. A/C service station refrigerant hose
   • From the low pressure side of the service station (mostly blue) to the output of the flushing device for refrigerant circuits.
3. Flushing equipment for refrigerant circuits
   • Different versions and different construction, for example Refrigerant Circuit Flushing Device -VAS6336/1- or Air Conditioning Flush Tool -VAS6337/1-.
   • With filter, viewing glass, security valve, heater, refrigerant container, etc. (depending on version).
   • Depending on the construction of the A/C service station and of refrigerant circuit flushing device, a check-valve may be installed at output of refrigerant circuit flushing device (to guarantee correct direction of refrigerant flow during flushing).
4. Charge hose for refrigerant circuit flushing device
   • From the high pressure side connection of the A/C compressor on the refrigerant circuit (smaller diameter) to input of Refrigerant Circuit Flushing Device -VAS6336/1- or Air Conditioning Flush Tool -VAS6337/1A-.
5. Adapter to connection for high pressure side on refrigerant circuit
   • The Refrigerant Circuits Adapter Set 1 - Adapter 3 -VAS6338/3- from the Refrigerant Circuits Adapter Set 1 -VAS6338/1-

Note

If the Refrigerant Circuits Adapter Set - Adapter 40 -VAS6338/40- is available, the filler hose can be directly attached to the A/C compressor.

6. High pressure side refrigerant line from A/C compressor

Note

Is not used if the Refrigerant Circuits Adapter Set - Adapter 40 -VAS6338/40- is available.

• Remove the centering pin from the refrigerant line so that the Refrigerant Circuits Adapter Set 1 - Adapter 3 -VAS6338/3- fits.

7. Electrically-driven A/C compressor

• The A/C compressor is flushed in the flow direction (from the low pressure side input to the high pressure side output)
• So that as much refrigerant oil as possible is flushed out of the A/C compressor, the A/C compressor must be positioned so that the high pressure side output is as low as possible.

8. Low pressure side refrigerant line to A/C compressor

Note

Is not used if the Refrigerant Circuits Adapter Set - Adapter 41 -VAS6338/41- is available.

• Remove the centering pin from the refrigerant line so that the Refrigerant Circuits Adapter Set 1 - Adapter 6 -VAS6338/6- fits.

9. Adapter for connecting low pressure side to refrigerant circuit
   • The Refrigerant Circuits Adapter Set 1 - Adapter 6 -VAS6338/6- from the Refrigerant Circuits Adapter Set 1 -VAS6338/1-

Note

If the Refrigerant Circuits Adapter Set - Adapter 41 -VAS6338/41- is available, the filler hose can be directly attached to the A/C compressor.

10. A/C service station refrigerant hose
    • From the A/C service station high pressure side (mostly colored red) to the connection on the low pressure line, or directly on the A/C compressor with the Refrigerant Circuits Adapter Set - Adapter 41 -VAS6338/41-.