I posted a question last year asking what to look for as my battery was going dead over a few days. Well after replacing a frozen batt. and more dead batterys I have traced the problem to the radio circuit(sp). I pulled the large 20 amp fuse in the fuse box under the hood next to the firewall drivers side. Haven't been able to get back at it as I've had some health problems. Must have a bare wire or something under the dash. Any ideas?-Bill

 

What else does that 20A fuse protect? Just the radio??

 

Yes it appears that way as I unplug that fuse when I'm not using the truck and the batt stays up.-Bill

 

Do you have an aftermarket alarm or remote start? Most installers find the radio power to be the best place to hookup stuff like that.

 

Yes I have both. I will have to see if they work. I know my alarm system has a clip that hooks to the pos batt cable as it says thank you when I hook it up. Thanks for the heads up. -Bill

 

Jumping in here - because I've got an 07 V10, with an aftermarket alarm and remote start and have been having the same problem. If I drive the truck daily (and I know what you're going to say about that), then it starts reliably. If it sits for more than a few days, there's a parasitic draw and the battery dies. How cold it is outside, dictates how long that takes.

I went out this morning and there wasn't enough to start it. This is maybe the 8th or 9th time this has happened (in the nearly 2 years I've had this problem).

When I went deer hunting early November, I pulled the negative cable, and a week later connected it back up and it started just fine - no problems.

My dealer says if he starts a diagnostic, he can see it taking 8-9 hrs to trace, because I have done some mods (all taken from this site and followed to the letter)...so not having that kind of spare change, or the skills to diagnose it myself - I still have the problem.

KREWAT (or anyone else) - can you explain how, if an installer has tied into the radio for power, that affects the battery?? If I had the installer rewire to an accessory fuse or direct to the battery, would that eliminate that possibility?

I'm just grasping for answers here, but thought I'd jump in since it looks like I have exactly the same problem; and I had no idea where to look, until you mentioned the alarm/starter hooking into the radio.

Thanks

 

I had this problem with a 97 EXPY and it turned out to be a bad radio, replaced with a salvage yard radio and was fine.