I have a 2005 F150. About a 10 months ago my truck wouldn't start one day so I had to get it jumped by a tow truck because the battery was so dead. Then a couple of weeks later it died again after I let it sit for a few days without driving it. I had it towed to the dealer who couldn't find anything wrong with it. They charged the battery and said the battery was fine. One day after I let it sit for a couple of days again same thing happened. Had towed back to the dealer where they kept it for almost a week. They couldn't find anything wrong, nothing draining the battery while it sits. They replaced the battery with a new one anyways. Now yesterday after not driving my truck all weekend I go to start it and its dead just like before. I have no aftermarket anything on the truck accept for my sirius sattelite radio and the alarm that came with the truck(new). Not sure if it is factory or not(code alarm). Any ideas since the dealer cant find anything?

 

There has to be some type of current draw, or maybe your alternator is not supplying enough charge to the battery when your truck's in motion.

Dunno.

I'm sure your dealership would have checked it but, as a second opinion, get a reputable automotive electrical shop to mutlimeter [or the like] and see how much current is being pulled and from what source.

I had a similar problem one time, and my Soundstream amp was drawing enough current to drain the battery after about five days of not starting my ride. The amp would show "off" upon shutdown with the LED on the amp going out, but it was still pulling enough current to drain the 750CCA battery.

Good luck.

 

could try this...

turn the truck off and take a test light to all the fuses. The light will light up if there is a current flowing through it. Of course some of them will have a current through it(radio memory, etc). Use the manual or this website to figure out the fuses. Hope this helps some, it may be a way to narrow it down to something....or at least a system.

I had a drain in my car that was driving me nuts, turned out it was the glove box light!!! I found it through the above method.

 

I'd start by checking if the sirius or alarm is drawing since those are the only 2 aftermarket add ons.

 

Take it to another dealer as well! But I agree, you have a current draw somewhere!

 

I had the same problem a few months ago. The battery would take a charge but it would not hold a charge for more than a day. Dropped it off at the dealership and they ran draw tests, tested the battery, and alternator. Could not find nothing wrong with it, even though the battery had a red eye. After getting a little angry, the service writer told me that next time it went dead to have it towed in. Thats what i did and they ended up replacing the battery, and problem solved!

Or you could save the hassle and go buy another one. I was under warranty.

 

I too had this issue, new battery from Ford, same problem, they say I must have a draw, they tested it and said my battery was fine and they couldn't find a draw. They also told me to have it towed in but the next time it died it was -30 C so when the temps dip that low tow trucks can be a 48 hour + wait. I got sick of dealing with it, so my brother boosted me and I went and bought an aftermarket battery. Have not had a problem since.

 

Thanks guys! I had it towed in. We'll see what they say.

 

I figured that sense Ford spent money having it towed in, there better be something done with it.