Do not hold the steering wheel fully turned in either direction for more than five seconds. This can damage the steering pump.
2. The reservoir of the power steering system is located in the engine compartment and has a screw cap with a measuring probe built into it.
Model 320d: Oil reservoir cap (arrow illustration) located in front of the oil level gauge when viewed in the direction of travel.
Petrol models: The reservoir is located in the area between the engine and the radiator.
3. Park your vehicle on level ground and apply the parking brake.
4. On a cold engine, the fluid level should be near the MIN·mark. Permissible deviation of the liquid level on the probe from the MIN·mark±2 mm.
5. Start the engine and warm it up to normal temperature. With the engine idling, turn the steering wheel from lock to lock several times to purge air from the steering system. Stop the engine, remove the tank cap by turning it counterclockwise, wipe the dipstick dry and close the cap. Open the cap again and check the fluid level. It should be between two marks.
6. Add liquid in small doses until it reaches the desired level.
Do not overfill liquid. If this does happen, remove the excess with a clean syringe. Close the lid.
7. If frequent topping up is required, check power steering hoses and fittings for signs of wear and leaks (refer to Section Check of a condition and replacement of hoses of an impellent compartment).
8. Check the condition and tension of the drive belt (refer to Section Checking the condition of drive ribbed belts).