Its has not happened to with the X5 but happened several times with my E46, someone in here suggested removing battery cables overnight, but that didnt help either, some said the 'sensors' have no clue bout it, I havent taken it to BMW as I dont use it frequently and besides need to have a good balance in my account.

My big worry with you is, if it happened there is a high probability (almost closer to 1) that it will happen again!, the bad weather is one thing, 'Gone in seconds' is another!

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