I have a 2004 F150 5.4L that gets a dead battery overnight. Installed new battery & new alternator and still dead overnight. Once started, works normal all day. I believe I have a parasitic draw. Letting the truck rest over an hour, then pulled the negative battery cable and received a 1.07amp draw for a minute. Then it goes to zero. I know it shouldn't be zero since the clock and computer should have a minimal draw. Checked over a week & same. Waited hours and still shows zero amp draw. Pulling fuses didn't change draw. Battery, when charged will show 12.4-12.6V. Looking for some help please.

 

Leave the battery cable off overnight and see if the battery is dead in the morning. If it is then you have a new BAD battery. If it's good then you may have a parasitic power draw. I've posted on here many times about the JUNK batteries that Johnson Controls makes after they bought out most of the other US battery manufacturers. JC makes most BRAND batteries today regardless of who's name is on the label.

Depending on how low the scale your amp meter goes to, it may look like 0 amps but most likely it's still pulling 1/10 of an amp or so. That's normal.

 

I'll pull the cable tonight & check in the morning. Thank you.
Regarding the multimeter. I used a cheap one (cen-tech) and had an old analog meter, both showed zero. Purchased a Klein that can read 0.000 amps, which caught the immediate draw. Thanks for the help and will checkup tomorrow.

 

Let us know what you find out.

 

Make sure the lights are all turning off when you lock up in the evening. I had an issue where the key in the ignition would not completely turn the truck off, thus leaving the radio on for extended time. I have to make sure now that the key is all the way in the "off" position before I pull the key out and lock the truck.

 

Verified everything was off. 2 more days in a row, my truck didn't start and needed a jump. Again, once started, it runs great. Alternator at 14+ volts until battery charged. (Have a new battery and new alternator). Let the truck sit for an hour and still can't locate any parasitic draw. Couple times found draws for a few minutes, but then everything went off and zero draw. There wasn't even a draw for the computer. I did see a video on a parasitic draw that happened about every 2 hours and the cause was the on-board computer. Let me know your thoughts people.

Thanks

 

Not sure if this is the video you mentioned you saw but it is very similar to your issue and it ended up being the alternator. Hopefully it can help you

 

The video I mentioned before was on an Audi, but has the same outcome. I just replaced the alternator and will check the temperature on it...I do have a thermal scanner. At least I would know if it's the alternator or not still. But why would the alternator power-on hours later and no key in the ignition?

I just checked the temperature on the alternator, same as everything else in the engine compartment. Also checked the charge on the battery; 12.4v. It was 12.6v a couple hours ago. Either way, I'll check in the morning & note any changes.

Thanks for all your input and I know we're getting closer to the problem.

 

It's not your alternator. You have a bad battery.

 

How do you know the battery is good? Load test?