Update--am in the garage. 2 days ago after I shut it off I checked the voltage at the under the hood terminals. All was fine. Today there is no power to anything. My battery charger will not start a charge cycle because it does not sense there is a battery to charge. The hatch is closed and I can't read codes. Before I climb in and remove all the nitrous stuff and subwoofer so I can start the painful process of getting to the battery from the back seat to see what it reads, expecting it will read 12volts as it has previously, any other suggestions? Is it possible that a bad EWS will cause this? I have never experienced not being able to charge or read battery voltage from the front terminals.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas