Hello, complete novice here. I inherited a low mileage 2002 Ford F150 4x4 with the 5.4l. It only has 94,000 miles on it. I have kept up on all maintenance with the help of the local dealership, but in the last two months my battery simply dies without warning. I started up fine, drove to the store, came out, no lights, no bells no anything when I turn the key. Starts with a jump but then dies when I am back home. When I try to start it I hear clicking under the dash and in the driver door. Even after I take the key out. Took the first battery to AutoZone, they tested it, replaced it under warranty. But now it has been almost two months and it has done it again. Almost exact same scenario. Any ideas what the problem could be?

 

Welcome to the forum!

Parasitic draw somewhere, like a faulty relay draining the battery? I'd suggest hunting down where exactly the clicking noise is coming from, and having the alternator properly tested. Also, check/clean/tighten all the grounds and battery cable connections/terminals.

 

Welcome.