Electric power/battery problem

I have a 1998 3.8 liter Windstar.

When I went to start the car this morning, there was no power to anything-
no interior lights, no open door chime. I assumed this was a dead battery,
and pulled it out to recharge it, but the voltage read 11.7, so after checking it with a 12v test lamp, I assumed that it was OK. I also cleaned the terminals.

On reinstalling it, the dome lights flickered off and on for a few minutes, and
the "open door" chime sounded. The voltage, connected, then read 10.6. with the ignition off, 3.9 with the ignition on (i don't know if this is normal or not), and after an hour or so of being connected, now reads 9.5 with the negative disconnected.


Does this indicate a drain or a short somewhere-- that perhaps didn't begin
until a short time before I went to start it?

Some clues-- I have been having a problem with the dome lights for a while-- they stay on until I reach 15mph, and also after Ipark, for 30 minutes (when the battery saver kicks in). The 'door open' light also stays
on, intermittently, even when there is no door open. But this has been
happening, usually in warmer weather (over 50) for a few years, without affecting anything else
.

Any suggestions about what to look for, and how? (I am now recharging the
battery.)

The dome lights staying on until you get to about 15mph is a common issue.....a door sensor is indicating that a door is open.....usually a dirty/sticking contact.
First thing to do is to check and clean the push button contacts and the mating contacts on the sliding door(s).
The contacts for the front doors are in the latch (not up front where they were years ago).
The switch is located just below the door latch.....the part that holds the door closed.
Here is a link to a picture that I took inside my front door.....take note that the slide rail for the window is removed.....as I took advantage of the oportunity to take this picture when I was replacing my broken slide rail......pretty hard to see with that rail in there.
http://rides.webshots.com/photo/2088597480011220610NnZmLd

The picture just before it is my attempt to get a picture with the rail in place.

I have tried to spray some WD-40 down into the switch through the latch area.

There are also sensors for the rear hatch.

As far as the voltage issue......cleaning the battery terminals/connections was a good first step.....there is also the connection at the starter......and the ground connection right next to the starter.
I am at this point thinking the battery could be problematic.
Certainly if it is over 5 years old......I would replace it.
If it is new.....if you have another battery to put in to see if it cures the problem.....if not......you could try getting it load tested.
Batteries can have strange ways of failing.

I would also check into the alternator condition.....a failing battery places an extra load on the alternator....which can cause it to fail.
The voltage regulator is a part of the alternator assembly.

I have a "Duralast Gold" from AutoZone....resonable price.....it is their "premium" battery and was highly rated last I looked.
I try to get the most powerful battery that I can......and get a "premium" battery as the cost difference is not much......and I think that it is worth getting a good one.

Hi izbeaver,

Sounds like your battery was discharged if it read under 12 volts. A fully charged battery should read 12.7 volts; 75% charged 12.4 volts; 50% charged 12.2 volts and 25% charged 12.0 volts. It's always best to charge a dead battery with a battery charger as car alternators just are not made to put out the load it takes to charge one from dead. Even new batteries should be fully charged before installing them.

Your battery showed typical voltages of a discharged battery showing near 12 volts but dropping rapidly when a load is applied.

Now, if that is due to a bad battery or just discharged battery from something like a dome light drain is where you are now. Have it tested after charging it.

When you install it you can check for parasite drain with an ammeter as described here (http://www.wikihow.com/Find-a-Parasitic-Battery-Drain). http://www.wikihow.com/Find-a-Parasitic-Battery-Drain

Wiswind's advice is great.

Thanx to both of you.

The battery is only 18months old charged up overnight to 12.87, and i will now do further testing, and let you know what happens.

Here's what's happening:

After reinstalling the battery, which took and held a full charge, I checked the
charging voltage: 14.65, idling, and and after headlights were on for a few
minutes. So I conclude that both the battery and alternator are OK. Before
taking it for a spin, I gave all the door latches a dose of WD-40.

The problem is somehow related to temperature-- vehicle and/or outside.
It also involves several electrical components-- door open indicator, chimes,
remote door unlock, interior (dome) lights, anti-theft system, and battery saver relay, and perhaps others:

-when the vehicle is cold and/or it is cold outside, if i open and then close a door, the door chime sounds, the dome lights will go out in a few seconds. I can then set the alarm with the remote control-- one loud horn sound-- and the alarm set indicator light will appear: all this seems normal.

-but returning after my test drive, the above does not happen. Instead, when I open the door, the chime does not sound, and the dome lights do not
go off until the battery saver kicks in in 30 minutes. I also cannot set the
alarm: I heard two horn sounds instead of one, and the alarm set indicator
did not appear. But after a half-hour, the lights went out.

- this has happened before, and I have adjusted to it, and have relied on
the battery saver to be able to start up in the morning. I suspect, but am
not sure, that the night this happened, somehow the battery saver did
not kick in-- perhaps because it was warmer outside. (One other thing
that has happened several times in the last few weeks is that the alarm will
go off for no apparent reason; I don't know if it has happened when i am not
nearby, but if so, i understand that it would go off within 4 minutes).

Any ideas about how to fix this? Thanx for your help!



1998 Windstar 3.8
186,000 miles

Check your negative battery cable. I had to replace mine on my '98 3.8L GL. Make sure you've got a good ground connection.