Car sat all winter an is now dead and wont start

NIKKIGAGNON

MEMBER
1999 MERCURY MOUNTAINEER
V8
AWD
AUTOMATIC
112,000 MILES

The car worked fine prior to sitting all winter, but I was in the hospital have massive surgeries so I let the car sit.. How do I get my key to turn over on mercury mountaineer. It makes zero noise, no lights. Odd is the battery was fairly new. I need major help. I tried jumping it once and it did start but maybe we didn't charge enough because as soon as I allowed the SUV to idle on for 20mins after jump. I turned it off and on once again wouldn't turn on. Should I try again but how would you do it or is it something else? ~Nikki G from OOB Maine

1 Reply

CARADIODOC

MECHANIC
33,742 POSTS

The battery can only be expected to hold enough charge to start the engine after sitting for three weeks. After a year it is going to totally dead. That's due to the memory circuits of all the numerous computers that constantly draw some current. If it froze during the winter, it will need to be replaced. If it didn't freeze, there is a chance it can be revived but you're going to have to put it on a charger at a slow rate for a minimum of an hour. It is going to take about fifteen minutes for it to START taking a charge. The acid in it has to have time to become conductive. If your charger has an amp meter, you'll see it start out at 0 amps, then after ten or fifteen minutes the current will gradually increase to around a maximum of 20 amps. It can be considered fully-charged when the current comes back down to around five amps.