Dead Battery 05 F150

[Fly_By_U]

My 05 F150 Lariat keeps draining the battery to nil after sitting idle for two weeks or more without use. Dealer replaced battery once, but problem still remains. Anyone else seeing similar problem or known cause?

Great truck otherwise, but this problem has the dealer stumped..

[rdsteele]

One method that I have used in the past with great success is to disconect the battery ground cable, then install a decent quality multimeter in series (set to the 10 amp scale) between the battery negative and the negative post on the battery (do not try to start) if the circuit causing the drain is active you will register a reading on the ammeter, probably a vey small reading of less than one amp if it take a couple weeks to drain the battery. Most likely it is an auxillary (add on) circuit causing the drain, simply remove one fuse at a time then check the meter, once the reading becomes zero you have found the guilty circuit.

[Fly_By_U]

Thanks for the suggestion. I was hoping someone had experienced this already before going the amp/circuit route. Auful lot of circuits and the box isn't that easy to access. Typical draw on the battery running about 1.6 amps just sitting and I've tried a few of the more obvious circuits that may require current when idle, but nothing yet. I have a bunch left. Typicaly when you connect the amp meter, it jumps a few amps on initial connection, then drops to .45 amps for a second or so then returns to 1.6 amps as steady state. Pain in the butt, but I don't think the dealer would perform individual circuit tests unless I keep bringing it in for service, which is a hassle in itself. Asked if they had Ford spec for idle current and they went blank....we don't have that information. Well go out and test one of those 200 or so damn trucks you have sitting out on the lot!!

So my $41K expensive lawn ornament trek continues...stay tuned..

[wreedKR]

Fly By U,
Did you ever find what was causing the draw?