Same thing happend to me the other day but the light went away. I checked and did not see any lights out. The warning has not come back on since. I am bringing it in for a service in the next few weeks anyway so I will have them check it out.

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'06 Porsche Cayenne Turbo S
Marine Blue/Sand on 22"s
'02 Porsche 996TT Ruf 550 Rturbo
Guards Red/Black
'04 X3 2.5i
Black/Black(Wife's) on X5 20's
'07 BMW 328xi Coupe
Crimson Red/Black (Wife's)