Checking pressure drop in cooling system
WARNING: This page is about a different car, the 2013 BMW X5 M, 2012 BMW X5 M, 2011 BMW X5 M, and 2010 BMW X5 M. However, it is still accessible from the selected car via links, so may be relevant.
Open the sealing cap on the coolant expansion tank. Fit special tool 17 0 101 / 17 0 113 .
BUILD UP EXCESS PRESSURE and wait approx. 2 minutes.
Cooling system is impervious to watertightness if pressure drop is max. 0.1 bar.