It happened to me twice in the last 4 months. It has been fine for the last 2 months. Not sure what happened, but it works now.

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2008 BMW X5 4.8i/Space Gray Metallic/Gray Nevada Leather/Dark Burl Walnut Wood Trim/Sport Package/Premium Package/Cold Weather Package/Technology Package/Ipod and USB Adapter/Running Boards/Satellite Radio

Retired: 2004 325i Orient Blue/Sand Leather/Wood Trim/SMG/Premium/Sport/Navigation/Xenon/Premium Sound