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2003 Ford Explorer - Battery drain

Battery replaced, alternator replaced, battery drained I;4 days of sitting in Parking Lot. Car has 85,000. Miles, always serviced by dealer

Parasitic power drain from SOMEthing in the SUV after the key is turned off. Usually aftermarket stereos, alarms or remote starters. Any competent mechanic can run a parasitic draw test to find the offending item.


With the emphasis on competent

I’ve had many colleagues tell me 500 milliamps of parasitic draw is acceptable

Not so

50 milliamps or less is acceptable

1 Like

Holy moley! 1/2 an amp will drain a 70 amp-hour battery to the point it won’t start a car in about 48 hours or less!

Yeah, when that guy . . . who’s been turning wrenches for 25 years or so . . . told me that, I just shook my head and walked away :frowning_face: