adman01

Ok, so I have a 2008 F-150 limited editon, for the past couple days Ive been waking up to a dead battery, so naturally I read through some forums and found some good advice, however I have not been able to find answers to all my questions. I pulled the positive lead of the battery and put an ammeter in series, allowed it to sit for approximately 30 minutes to ensure there was nothing drawing from initial battery hook up. Im drawing 600 milliamps! All the forums and common sense tells me this is way to much, so start with the easy thing, pulling fuses. I pull F110 ( Cigar lighter, Diagnostic connector power) and it drops approx. 40 mA, I have an EDGE Evolution controller hooked up, so I disconnect it and sure enough thats one draw, easy enough, Im assuming these things have a continuous draw for memory ( couldnt find a power consumption table for it but 40 mA sounds about right). Next I pull F102 (Ignition switch feed) its drawing about 40 to 50 mA as well, this one I have no idea about, is this normal ? And lastly I pull F21 (Cluster keep alive power ) and it drops about 480 mA, wow!, now according to the Haynes repair manual this fuse feeds into the guage cluster, but so do four others and it doesnt say exactly what I could disconnect to troubleshoot. With all these disconnected im drawing about 20 mA total so I think F21 and F102 are the culprits. So Im left with either pulling my whole guage cluster apart or hopefully someone on here with a better recommendation, hope to hear from someone.

Pity7700

geez, battery drain sucks. have you changed anything to the vehicle electrically recently?

35-50 mA is the range of normal draw.

adman01

And to add, no I have'nt done any work on it as of late, my battery froze about 3 weeks ago so I changed it out, it's been good up until 3 nights ago.

roachie13

I have a 2005 Lariat with the same problem. Did you ever find a fix?

If I disconnect the instrument cluster, the draw drops almost 500 mA. Local dealer told me the problem is a computer in the IC won't shut down and the only fix is to replace the entire thing at $453 for the part and $180 for labor and software load. Is there a timed relay somewhere in the IC keeping the computer on? Haynes manual is not detailed enough to troubleshoot further.

My current solution is to pull F21 every time I park and reinsert it when I want to go somewhere.

cgrable

I'm currently having to do the same thing with my F-150. If I don't reset that fuse then the battery will be dead in a few hours. Also funny thing, I hit lock on my doors and the driver side unlocks itself.. strange.. Of course folks are saying I need to replace the computer for the low low price of 1k.. Please HELP!!!

ChampaNova

Did you ever happen to find a solution to your problem? I am having the exact same issue for the past 8months now?

roachie13

I never really did anything to resolve the issue. I forgot to pull the fuse a couple days is a row and realized the battery was no longer going dead. Not sure what fixed the issue.

homer

I always ask people this.... Anything aftermarket? i.e. Remote starter? Technically if the remote starter was stuck on for ignition you'd see the lights but I've seen interesting things happen before.

lyricspap

I had this happen to me 2 weeks ago. had to have someone come give me a jump. but I decided to turn the radio off and lock the doors every night when I got home and it hasn;t happened again since. ?

jamie930

Sound like you have a bad accessory relay, or door switch. When you lock the doors it bypasses the time delay and shut every thing off. All the accessories should shut off after about 10 min

Headlights are in this too, so if you leave your lights you should not havea dead battery