battery drain?

[88Racing]

The other problem that I have seen is very very rare. I emphasize rare. Its called shut down sequencing failure. This is what happens when the modules don't talk to the pcm when shutting down. When we shut our vehicles down, especially the ones mfgd in the last 10 years, a lot more happens than just turning off the key. The pcm likes to put all the modules "to bed" but if one of the modules isn't responding due to a intermitent connection the pcm cycles back through all the modules. It will keep doing this until its satisfied or the battery goes dead. All because one module isn't responding.
I have only seen this on 4 vehicles in the last 10 years and sometimes its a PIA to diagnose! Especially when the intermitent connection is present. Why am I emphasizing intermitent? Because a faulty module will throw a code. An intermitent module may be connected or disconnented, long enough in the sampling cycle for a code not to be important. Most of the time to diagnose the vehicle will have to be at the dealer overnight, maybe for one visit or possibly for multiple visits. I have seen this in 2 gms, 1 dodge, and 1 ford. Usually if this is the problem everthing on the charging/supply side has been replaced including cables and maybe even the battery twice.
I am pretty sure the OP's problem isn't this.

Lars

[Jackpine]

That's an interesting problem Lars! (Ain't progress wonderful?)

One of the f150Online members had a fuel pump relay that didn't open properly at shutdown, which put a big draw on his battery. He had to have the whole distribution panel (fuse box) replaced to fix it (since it's part of the panel and not replaceable).

To RGSMDNR, the BatteryTender or BatteryMinder is really not difficult to use at all. They come with a "quick plug in" connector that you can attach permanently to the screws on the battery posts. Then attaching the maintainer is a simple matter of raising the hood and plugging the maintainer in. Takes all of 10 seconds. It's MUCH more convenient than unplugging and plugging in the Gryphon. If I'm going to change the tune in my PCM, I just leave the maintainer connected, that way I know the battery is being held at near full charge.

I actually prefer the BatteryMinder, since it has a desulfation circuit. Here's a link to their website: http://www.batteryminders.com/batter...o-p-16134.html

You can get them for around $42 online now I see. Sorry if it sounds like I'm selling them, I'm not. It's just that I see it as a perfect solution for trucks that sit for long intervals. There's no way, short of disconnecting the battery or pulling fuses that you can get rid of the truck's parasitic draw.

- Jack

[coolio4433]

Interesting that this is the case, but I suppose not entirely surprising. My truck sits for extended periods (especially in the summer when I drive my "summer only" car) and I finally had the battery drain to the point where it wouldn't start the other day. A quick jump and I was back on the road though.

My truck sits outside year round though so a battery tender isn't as good an option for me (especially so when it's parked on the street).

I guess I'll probably start unplugging the gyphon now to keep this from happening again. I also decided that the auto headlights (they come on when you unlock the truck when on that setting) are probably not helping either so I flipped those off.

Hopefully those will do the trick, but I'm tempted to get a new battery before winter anyway. I hear the DieHard Platinum are top of the line. Anyone here have opinions?

-Matt