The following steps should always be carried out in the specified order before working in the engine compartment :

Park the vehicle on a level and stable surface.

Depress and hold the brake pedal until the engine has stopped.

Apply the handbrake firmly Braking, stopping and parking Brakes Parking .

Select the neutral position or move the selector lever to P Changing gear Changing gear Automatic gearbox see Automatic gearbox_0 Automatic gearbox see Changing gear_0 Automatic gearbox Manual gearbox see Changing gear_0 Manual gearbox .

Stop the engine and remove the key from the ignition Starting and stopping the engine Engine and ignition Ignition see Engine and ignition_6 .

Allow the engine to cool sufficiently.

Children and other people should be kept well away from the engine compartment.

Ensure that the vehicle cannot roll away unexpectedly.

WARNING
Preparing the vehicle for working in the engine compartment
Opening and closing the bonnetTwo-Part HS Wet-in-Wet Filler
Definition:
Two-Part HS Wet-in-Wet Filler -LVM 013 008 A4-, light gray
Two-Part HS Wet-in-Wet Filler -LVM 013 905 A4-, black
Edition 03/2015
Product Description
...
Antenna Wires, Repairing
Aerial Cable Repair Set -VAS6720
Special tools and workshop equipment
required
Repair Set, Aerial Cable -VAS6720-
Checking the Antenna Wire. Refer to
Replacing the Tool Head. Refer to
...
A/C System, Operating after Charging
Caution
If it is suspected that chemicals were added to the
refrigerant circuit to seal leaks, do not connect the
A/C service station and do not extract the refrigerant.
...