Warning! Do not open the refrigerant circuit in the air conditioner. The refrigerant contains substances that can cause frostbite when in contact with the skin.
1. Clean the level indicator (arrow) on the fluid reservoir.
2. Remove the plug connector from the temperature sensor (coolant/Air Conditioning) (B10/8) Shunt the connections with an auxiliary wire.
3. Start the engine and let it idle.
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4. Turn on the air conditioner and set it to the "Defrost" or "Air Dry" position.
5. Remove the jumper on the plug connector and watch through the peephole on the refrigerant tank. The refrigerant should rise briefly after the electromagnetic coupling is switched on and then flow without bubbles. In this case, the refrigerant may no longer be visible.
6. Slide the plug connector onto the temperature sensor.
Caution! At higher ambient temperatures (above +35°C), foam and some bubbles may appear even with the normal amount of refrigerant filling. In case of refrigerant leakage or suspected leakage of the system, the correct amount of refrigerant filling can only be determined by completely emptying and refilling the system (work in a car repair shop).