Bad alternater question

[tjr19136]

Can A bad alternater cause a battery to die while to car is off.........1 day I left my car in the on postion because I just was listen to the radio but, I took the key out while the car was still in the on position.. I didnt realize it intill the next day and I had to get a jump.........I letted the car run for a few minutes...........The next day I had to get a jump again, and i tested the alternater but dissconnecting the ground cable from the battery while the car was running and it cut off.........So I guessing I the alternater dead.

[emt1134]

First of all, you shouldn't be able to take your key out of the ignition in the RUN position, unless these cars have that feature.. I am not familiar with Lincolns...However, i can tell you that leaving your key on probably did drain your battery.. Although you got the jump and let your car run for a few minutes, this is not enough time for the alternator to fully charge the battery, which is why it would not restart. Your best bet would be to put a battery charger on it, or get another jump and drive down the highway for awhile. As for testing the alternator, removing the negative cable is not the way to test it.. removing the negative cable will disrupt current flow, which is why your car died when removing it.