I really do not KNOW why the X5 is an electrical hog, but I ALWAYS turn off EVERYTHING before turning off the ignition. My 2001 X5, I put in a new battery right after purchasing it 06/05, as it was a 12/00 build and thus the battery was almost 5yrs old with winter coming. Weak batteries always seem to die in cold weather. Batteries rarely last more than 5yrs, so I replace mine before winter if it is more than 4yrs old. Never had a replacement battery die on me in 40+yrs of driving. OEM batteries, on the other hand, I have had die on me early, with one not lasting a year. So taking your car in for a winterizing checkup (Sears, dealer, etc) can discover whether you have a weak battery, is not a bad idea.

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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