Special tools required:

WARNING: This page is about a different car, the 2003 BMW 525i, 2002 BMW 525i, and 2001 BMW 525i. However, it is still accessible from the selected car via links, so may be relevant.

17 0 002
17 0 005

Top up coolant.

Fig 1: Installing Special Tool To Expansion Tank

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Fit special tool 17 0 002/17 0 005 to expansion tank and develop a pressure of approx. 1.5 bar. Check cooling system for water leaks when doing so.

Fig 2: Locating Vent Plug

Courtesy of BMW OF NORTH AMERICA, INC.

Remove microfilter on left.

Open bleeder screw until bubble-free coolant emerges. Close bleeder screw, undo hose clip.

Start independent parking heater and wait for combustion. Start engine and run at 4000 RPM. The independent heating system assumes after-running mode. The circulation pump continues to operate. Within 2 minutes of starting engine, open and close bleeder screw on independent heating unit several times. Allow engine to warm up until thermostat valve opens. This completes the venting process. Turn off engine, allow to cool down and check coolant level; if necessary, draw off or top up.