Audi A4: General Information

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; Charging the Battery and → Electrical Equipment; Rep. Gr.93; General Notes for Working on the High Voltage System.

- Move the selector level into position "P", activate the parking brake and arrange the necessary tools for testing and measuring procedures that require the ready mode to be active or that require the ignition to be on, so that they cannot come into contact with the turning components in the engine and so that they are not in the vicinity of the turning components of a running engine.

  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 "powermeter". Refer to Owner's Manual.
• Activate and deactivate the ready mode. Refer to Owner's Manual (consult the display in the Instrument Cluster Control Module -J285-).

Vehicles with Start/Stop System

There is a Risk of Injury from the Engine Starting Unexpectedly

The engine can start unexpectedly on vehicles with an activated Start/Stop System. A message appears in the instrument cluster indicating whether the Start/Stop System is activated.

- Deactivate the Start/Stop System: Turn off the ignition.

All Vehicles

  Caution

• If it is suspected that chemicals were added to the refrigerant circuit to seal leaks, chemical substances to seal leaks in the refrigerant circuit (leak stop additive), do not connect the A/C service station and do not extract the refrigerant.
• Chemicals that seal leaks in the coolant circuit form deposits that affect the function of the A/C system and lead to failure of the A/C system and the A/C service station.
• Inform that customer that there are substances in the A/C system that are no approved by Audi.

  Note

• The chemical materials (stop leak additive) for sealing leaks in the refrigerant circuit offered on the market are not approved by Audi AG. There are no permanent- ,validity or material compatibility tests. Therefore, damage or malfunctions in the A/C system or the A/C Service Station cannot be excluded.
• The stop leak additives offered on the open market have different physical and chemical properties, which can impair the function of the A/C system and the A/C Service Station and can even shut down the system completely.
• Audi does not approve the use of chemicals to seal leaks in the refrigerant circuit (leak stop additives).
• Chemical materials (leak stop additives) to seal leaks in the refrigerant circuit react with air or the moisture in the air and form deposits in the refrigerant circuit (and in the A/C service station) that lead to malfunctions in the valves and other components that come into contact with such chemicals. These deposits cannot be removed completely from the components (also not through cleaning/flushing with refrigerant R134a).
• It is not possible to recognize chemical substances to seal leaks in the refrigerant circuit (leak stop additive) and the label that is supposed to come with them is usually not there. Therefore be careful when working with if you do not know its service history.
• Accessories offer containers used to separate out these chemicals (used to seal leaks in the refrigerant circuit). Since Audi does not know composition and the physical and chemical properties of these materials, it is not possible to make a statement about their effectiveness and the deposition rate of these filters.
• The Filter for Sealants -VAS6592- offers a certain protection for the A/C service station. This filter is incorporated between the A/C service station and the Service connection on the low pressure side of the refrigerant circuit in a vehicle (the A/C service station may not be connection to the service connection of the high pressure side of the refrigerant circuit for draining, evacuating and measuring). This filter separate certain materials that were added to seal leaks in the refrigerant circuit. It prevents these materials from getting into the refrigerant and refrigerant oil in the A/C service station unchecked and doing damage. For the protection to work, it is necessary that the filter be changed in regular intervals and exactly according to the manufacturer specifications (described in the instructions provided). Audi does not support using chemical materials (stop leak additives) for sealing leaks in the refrigerant circuit. There are many different formulas of these chemicals (stop leak additives), that are offered as "sealant for refrigerant circuits" and it is not possible to make a statement about the effectiveness of the Filter for Sealants -VAS6592-.

If the refrigerant circuit gets filed with a chemical material (stop leak additive) to seal any leaks (or if there is a suspicion of this) and if it then necessary to perform a repair to the refrigerant circuit, then it is necessary to inform the customer of the following:

• It is not possible to evacuate the refrigerant from the A/C system due to the stop leak additive that has been added to the system because it will damage the A/C Service Station. It will necessary to hire an outside company the can evacuate the contaminated refrigerant with a suitable device and then dispose of it (for example, a local waste management company that specializes in disposing of refrigerant).
• It will be necessary to replace any refrigerant circuit components that have come in contact with the stop leak additive in order to repair the A/C system properly. Certain refrigerant circuit components may already be damaged by the stop leak additive (for example, the A/C Compressor Regulator Valve -N280-) or will get damaged if they are used over again and will fail after a short amount of time. In addition to this, if there is any sediment from the stop leak additive still in the circuit, it could come loose at a later point and cause the A/C system to fail again (currently it is not possible to clean these components with any workshop tools).

Working on the A/C system refrigerant circuit

Refer to → Chapter "Service Station, Important Usage Information"

Refer to → Chapter "A/C Service Station, Connecting for Measuring and Testing"

Refer to → Chapter "Refrigerant Circuit, Discharging with Service Station"

Refer to → Chapter "Refrigerant Circuit, Discharging with Service Station"

Refer to → Chapter "Refrigerant Circuit, Charging with Service Station"

Refer to → Chapter "A/C System, Operating after Charging"

Refer to → Chapter "Refrigerant to Service Station Reservoir (Charging Cylinder or Reservoir Bottle), Transferring"

Refer to → Chapter "Service Station, Draining"

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