Sequence of works
1. Open the tank cap and remove it together with the dipstick.
Fig. 7.15. When the working fluid temperature is about +20°C, its level should be between the two marks on the dipstick
2. The level of the power steering fluid (at an air temperature of about +20°C) should be between the "MIN" and "MAX" marks on the dipstick (Fig. 7.15).
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3. If necessary, add power steering fluid (Mercedes-Benz 000 969 88 03). Use only new fluid, as even minimal contamination can cause hydraulic drive failure.
4. Reinstall the plug with the dipstick and tighten it.
5. Finally, bleed the power steering system by turning the steering wheel from lock to lock several times with the engine running.