If you're looking for a way to blame the car instead of your wife blaming you for this...you're on your own, pal.
It's a small battery that drains quickly...they weren't designed to run items without being charged at the same time. Intermittent operation of the engine would have prevented it.
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1987 560SL
85,000 miles
Meet on the level, leave on the square. Great words to live by
Were we directed from Washington when to sow and when to reap, we should soon want bread. - Thomas Jefferson: Autobiography, 1821.