Audi Q7: Guidelines for Clean Working Conditions
Even a small amount of contamination can lead to malfunctions. Therefore, observe the following guidelines for cleanliness when working on the A/C system:
- Immediately seal the open lines and connections with clean plugs, for example from the Engine Bung Set -VAS6122-.
- Place the removed components on a clean surface and cover them with lint-free cloths.
- Carefully cover opened components or seal if the repair cannot be performed immediately.
- Only install clean parts: Unpack replacement parts just before installing them. Do not use any parts that have been kept out of packaging (for example, in a toolbox).
- Do not work with compressed air when the system is open.
- Protect the disconnected connectors from dirt and moisture and only connect them when they are dry.
General Information
- The applicable wiring diagrams are found in → Wiring diagrams, Troubleshooting & Component locations.
- An information label in the engine compartment indicates which refrigerant is used and the capacity. Refer to → Chapter "Type Labels".
- Further information on repairing vehicles with an A/C system and handling refrigerant. Refer to → Refrigerant R134a Servicing; Rep. Gr.87; A/C System, General Information.
General Repair Information
WARNING
Before working on electrical system (wiring), remove relevant fuse(s).
Note
Disconnect the battery before performing any electric welding on the vehicle. Refer to → Electrical Equipment; Rep. Gr.27; Battery; Battery, Disconnecting and Connecting.
The refrigerant circuit for the A/C system may only be discharged and opened when:
- it is necessary due to safety precautions. Refer to → Chapter "Safety Precautions when Handling Refrigerant".
- it is necessary to remove other components,
- refrigerant circuit components for the A/C system must be removed or replaced.
When performing all other usual vehicle repair work, the refrigerant circuit of the A/C system remains closed.
Note
The connections for the sensors/switches described in this repair manual are fitted with a valve which closes automatically when the switches are removed. These switches can thus be replaced in any Audi and Volkswagen workshop even though the refrigerant circuit is fully charged.
If it is necessary to discharge and open the A/C system refrigerant circuit for certain repair work on the heating and A/C system, this is described in the respective work procedure. Certain tools are required to discharge the refrigerant circuit. Also, these work procedures may only be performed by trained personnel as well. Refer to → Refrigerant R134a Servicing; Rep. Gr.87; Refrigerant Circuit.
Note
If the necessary tools are not available or no qualified personnel is present, do not perform repairs on the refrigerant circuit for the A/C system that require the refrigerant circuit to be discharged and opened. If necessary, the vehicle must be transferred to a workshop that has the necessary tools and equipment and where the work can be performed by qualified personnel. There the refrigerant circuit can be discharged and opened according to the legal specifications. Refer to → Refrigerant R134a Servicing; Rep. Gr.87; A/C System, General Information.
Contact Corrosion
Contact corrosion can occur if inappropriate fasteners (bolts, nuts, washers, rivets, plugs, grommets, adhesives etc.) are used.
For this reason, the manufacturer only installs fasteners with a special surface coating. Also, rubber and plastic parts and adhesive consist of materials that do not conduct electricity. These parts, which have been tested and are aluminum compatible, are also available as replacement parts. Refer to the Parts Catalog.
Note
- Always install new parts if there is any doubt as to whether parts can be reused.
- Original equipment replacement parts are recommended. They have been tested and are compatible with aluminum. Refer to the Parts Catalog.
- Audi accessories are recommended. Refer to Parts Catalog.
- Damage due to contact corrosion is not covered by warranty.
Line Routing and Securing
- To avoid confusion and to ensure the original installation location, mark the lines/hoses for fuel, hydraulics, vacuum, EVAP system or electrical wires before removing. If necessary, draw sketches or take pictures.
- Due to the tight working conditions, make sure there is sufficient clearance in the engine compartment for all moving or hot components to prevent damaging the lines.
- Check the routing of the refrigerant lines after attaching. They must be inserted into the provided brackets and must not come in contact with other components.
Radiator and Condenser Assembly
- The radiator and condenser may have small indentations on the fins even when installed correctly. It is not damage. Do not replace the radiator or condenser because of those small indentations.
- Slight deformations on the side condenser securing straps (for example, due to an accident) that result in an unparallel flow from the condenser and radiator can be repaired by pulling the straps back as long as the function/condenser sealing is not impaired. The condenser does not need to be replaced if there are small deformations on the straps.
- A slight bending of the condenser (up to 4 mm) is permissible as long as there is sufficient distance (minimum 4 mm) between the condenser and the radiator and the function/sealing of the condenser is not impaired. The condenser does not have to be replaced if there are slight deformations.
