Control Module HVAC: Service Precautions

General Repair Information

Vehicles with Start/Stop System

On vehicles with the Start/Stop System, the engine could start automatically causing serious personal injury.

• If the Start/Stop System is activated (recognizable by a message in the instrument cluster), it is possible to start the engine automatically.

• Make sure the Start/Stop System is deactivated is deactivated (ignition switched off) whenever working on the vehicle.

All vehicles

Before working on the electrical wires, remove the relevant fuse(s).

• Disconnect the battery before starting electric welding work on vehicle.

The refrigerant circuit of the A/C system must not be discharged and opened => [ Refrigerant Circuit, Draining ] Refrigerant Circuit, Draining unless it is necessary because of safety precautions => [ A/C and Refrigerant Safety Precautions ] A/C and Refrigerant Safety Precautions or components of the refrigerant circuit of the A/C system have to be to replaced.

When performing all other usual vehicle repair work, the refrigerant circuit of the A/C system should remain closed.

Servicing operations that can be performed on the heating and air conditioning system without opening the refrigerant circuit are described in this repair information. Refer to => [ Refrigerant Circuit Components Overview ] Refrigerant Circuit Components Overview , => [ A/C System Control and Regulation Components Outside Passenger Compartment ] A/C System Control and Regulation Components Outside Passenger Compartment and => [ A/C System Control and Regulation Components Inside Passenger Compartment ] A/C System Control and Regulation Components Inside Passenger Compartment.

• The connections for the senders/switches described in this Workshop Manual are fitted with a valve which closes automatically when the switches are unscrewed. These switches can thus be replaced in any Audi and Volkswagen workshop even though the refrigerant circuit is fully charged.

Service work on the A/C system that requires the refrigerant circuit to be discharged, and thus cannot be performed in every Audi and VW workshop, is described starting in => [ Refrigerant Circuit Components Overview ] Refrigerant Circuit Components Overview. Certain tools are required to discharge the refrigerant circuit, these work procedures must only be performed by trained personnel as well. Therefore, bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel if necessary.

• Refer to => [ Contact Corrosion ] Contact Corrosion

• Refer to => [ A/C Components Controlled or Activated by Other Control Modules ] A/C Components Controlled or Activated by Other Control Modules

• Refer to => [ Components Actuated by A/C System ] Components Actuated by A/C System